CHI '20: Proceedings of the 2020 CHI Conference on Human Factors in Computing Systems

Full Citation in the ACM Digital Library

Introducing Peripheral Awareness as a Neurological State for Human-computer Integration

In this work we introduce peripheral awareness as a neurological state for real-time human-computer integration, where the human is assisted by a computer to interact with the world. Changes to the field of view in peripheral awareness have been linked with quality of human performance. This instinctive narrowing of vision that occurs as a threat is perceived has implications in activities that benefit from the user having a wide field of view, such as cycling to navigate the environment. We present "Ena", a novel EEG-eBike system that draws from the user's neural activity to determine when the user is in a state of peripheral awareness to regulate engine support. A study with 20 participants revealed various themes and tactics suggesting that peripheral awareness as a neurological state is viable to align human-machine integration with internal bodily processes. Ena suggests that our work facilitates a safe and enjoyable human-computer integration experience.

Venous Materials: Towards Interactive Fluidic Mechanisms

Venous Materials is a novel concept and approach of an interactive material utilizing fluidic channels. We present a design method for fluidic mechanisms that respond to deformation by mechanical inputs from the user, such as pressure and bending. We designed a set of primitive venous structures that act as embedded analog fluidic sensors, displaying flow and color change. In this paper, we consider the fluid as the medium to drive tangible information triggered by deformation, and at the same time, to function as a responsive display of that information. To provide users with a simple way to create and validate designs of fluidic structures, we built a software platform and design tool UI. This design tool allows users to quickly design the geometry, and simulate the flow with intended mechanical force dynamically. We present a range of applications that demonstrate how Venous Materials can be utilized to augment interactivity of everyday physical objects.

Considering Parents in Coding Kit Design: Understanding Parents' Perspectives and Roles

As education researchers, policymakers, and industry leaders recognize the importance of computing, many coding kits (toys and apps) have emerged to help young children learn to code at home. However, how parents perceive and support their children's use of the kits at home are less understood. In this study, we performed semi-structured interviews with eighteen parents who obtained coding kits for their young children for home use. The results show parents expected their kids to have fun and meaningful interactions with the kits. In supporting the play, parents took on various roles, mostly acting as spectator, scaffolder, and teacher. While parents perceived benefits of coding kits like a changed perspective on coding, they also reported concerns, such as their limited programming knowledge to provide help. Finally, we reflect on design and research implications to develop coding kits that consider parents' perspectives and important roles in supporting young children's exploration with computational thinking.

If I Hear You Correctly: Building and Evaluating Interview Chatbots with Active Listening Skills

Interview chatbots engage users in a text-based conversation to draw out their views and opinions. It is, however, challenging to build effective interview chatbots that can handle user free-text responses to open-ended questions and deliver engaging user experience. As the first step, we are investigating the feasibility and effectiveness of using publicly available, practical AI technologies to build effective interview chatbots. To demonstrate feasibility, we built a prototype scoped to enable interview chatbots with a subset of active listening skills-the abilities to comprehend a user's input and respond properly. To evaluate the effectiveness of our prototype, we compared the performance of interview chatbots with or without active listening skills on four common interview topics in a live evaluation with 206 users. Our work presents practical design implications for building effective interview chatbots, hybrid chatbot platforms, and empathetic chatbots beyond interview tasks.

BlyncSync: Enabling Multimodal Smartwatch Gestures with Synchronous Touch and Blink

Input techniques have been drawing abiding attention along with the continual miniaturization of personal computers. In this paper, we present BlyncSync, a novel multi-modal gesture set that leverages the synchronicity of touch and blink events to augment the input vocabulary of smartwatches with a rapid gesture, while at the same time, offers a solution to the false activation problem of blink-based input. BlyncSync contributes the concept of a mutual delimiter, where two modalities are used to jointly delimit the intention of each other's input. A study shows that BlyncSync is 33% faster than using a baseline input delimiter (physical smartwatch button), with only 150ms in overhead cost compared to traditional touch events. Furthermore, our data indicates that the gesture can be tuned to elicit a true positive rate of 97% and a false positive rate of 1.68%.

Making Space for Social Sharing: Insights from a Community-Based Social Group for People with Dementia

People with dementia face major challenges in maintaining active social interaction. Designing digital tools for social sharing within families and care facilities has been well explored by HCI research, but comparatively less work has considered community settings. Situated in a community-based program for storytelling and socializing, our field observations and semi-structured interviews with people living with early-middle stage dementia, family caregivers, and program facilitators illustrate both positive and challenging aspects of social activities. We contribute a nuanced understanding of participants' social lives and identify four factors that aid in achieving positive outcomes: effective agencies for social interaction, normalized and friendly environments, collaboration and teamwork, and mediating social cues and communication. Finally, we examine our findings through the lens of past HCI work and offer insights for designing new social technologies to diversify the range of social spaces in community settings, through expanding peer collaboration, leveraging physical and virtual spaces, creating open-ended experiences, and developing flexible platforms.

Phasking on Paper: Accessing a Continuum of PHysically Assisted SKetchING

When sketching, we must choose between paper (expressive ease, ruler and eraser) and computational assistance (parametric support, a digital record). PHysically Assisted SKetching provides both, with a pen that displays force constraints with which the sketcher interacts as they draw on paper. Phasking provides passive, "bound" constraints (like a ruler); or actively "brings" the sketcher along a commanded path (e.g., a curve), which they can violate for creative variation. The sketcher modulates constraint strength (control sharing) by bearing down on the pen-tip. Phasking requires untethered, graded force-feedback, achieved by modifying a ballpoint drive that generates force through rolling surface contact. To understand phasking's viability, we implemented its interaction concepts, related them to sketching tasks and measured device performance. We assessed the experience of 10 sketchers, who could understand, use and delight in phasking, and who valued its control-sharing and digital twinning for productivity, creative control and learning to draw.

Peer-to-Peer Energy Markets: Understanding the Values of Collective and Community Trading

Peer-to-peer energy-trading platforms (P2P) have the potential to transform the current energy system. However, research is presently scarce on how people would like to participate in, and what would they expect to gain from, such platforms. We address this gap by exploring these questions in the context of the UK energy market. Using a qualitative interview study, we examine how 45 people with an interest in renewable energy understand P2P. We find that the prospective users value the collective benefits of P2P, and understand participation as a mechanism to support social, ecological and economic benefits for communities and larger groups. Drawing on the findings from the interview analysis, we explore broad design characteristics that a prospective P2P energy trading platform should provide to meet the expectations and concerns voiced by our study participants.

AirTouch: 3D-printed Touch-Sensitive Objects Using Pneumatic Sensing

3D printing technology can be used to rapidly prototype the look and feel of 3D objects. However, the objects produced are passive. There has been increasing interest in making these objects interactive, yet they often require assembling components or complex calibration. In this paper, we contribute AirTouch, a technique that enables designers to fabricate touch-sensitive objects with minimal assembly and calibration using pneumatic sensing. AirTouch-enabled objects are 3D printed as a single structure using a consumer-level 3D printer. AirTouch uses pre-trained machine learning models to identify interactions with fabricated objects, meaning that there is no calibration required once the object has completed printing. We evaluate our technique using fabricated objects with various geometries and touch sensitive locations, obtaining accuracies of at least 90% with 12 interactive locations.

Digital Liminalities: Understanding Isolated Communities on the Edge

This paper brings together three distinct case studies to explore how social isolation and notions of liminality shape ontological security within communities on "the edge" of society. Each case study exemplifies the differing nature of liminality in everyday contexts and the extent to which increased digitalisation perturbs it in multiple ways. Taking an ethnographic approach, the research engaged with seafarers onboard container ships in European waters, communities in Greenland and welfare claimants in the North East of England. It posits that technological innovation must attend to the routinisation of everyday life through which people establish ontological security if such innovation is to be supportive. The paper thus moves beyond existing HCI scholarship by foregrounding the contextual and relational aspects of social isolation rather than the technological. It does so by advocating a ground-up design process that considers ontological security in relation to notions of liminality among communities on the edge.

Mouillé: Exploring Wetness Illusion on Fingertips to Enhance Immersive Experience in VR

Providing users with rich sensations is beneficial to enhance their immersion in Virtual Reality (VR) environments. Wetness is one such imperative sensation that affects users' sense of comfort and helps users adjust grip force when interacting with objects. Researchers have recently begun to explore ways to create wetness illusions, primarily on a user's face or body skin. In this work, we extended this line of research by creating wetness illusion on users' fingertips. We first conducted a user study to understand the effect of thermal and tactile feedback on users' perceived wetness sensation. Informed by the findings, we designed and evaluated a prototype---Mouillé---that provides various levels of wetness illusions on fingertips for both hard and soft items when users squeeze, lift, or scratch it. Study results indicated that users were able to feel wetness with different levels of temperature changes and they were able to distinguish three levels of wetness for simulated VR objects. We further presented applications that simulated an ice cube, an iced cola bottle, and a wet sponge, etc, to demonstrate its use in VR.

Replicate and Reuse: Tangible Interaction Design for Digitally-Augmented Physical Media Objects

Technology has transformed our physical interactions into infinitely more scalable and flexible digital ones. We can peruse an infinite number of photos, news articles, and books. However, these digital experiences lack the physical experience of paging through an album, reading a newspaper, or meandering through a bookshelf. Overlaying physical objects with digital content using augmented reality is a promising avenue towards bridging this gap. In this paper, we investigate the interaction design for such digital-overlaid physical objects and their varying levels of tangibility. We first conduct a user evaluation of a physical photo album that uses tangible interactions to support physical and digital operations. We further prototype multiple objects including bookshelves and newspapers and probe users on their usage, capabilities, and interactions. We then conduct a qualitative investigation of three interaction designs with varying tangibility that use three different input modalities. Finally, we discuss the insights from our investigations and recommend design guidelines.

FDHelper: Assist Unsupervised Fraud Detection Experts with Interactive Feature Selection and Evaluation

Online fraud is the well-known dark side of the modern Internet. Unsupervised fraud detection algorithms are widely used to address this problem. However, selecting features, adjusting hyperparameters, evaluating the algorithms, and eliminating false positives all require human expert involvement. In this work, we design and implement an end-to-end interactive visualization system, FDHelper, based on the deep understanding of the mechanism of the black market and fraud detection algorithms. We identify a workflow based on experience from both fraud detection algorithm experts and domain experts. Using a multi-granularity three-layer visualization map embedding an entropy-based distance metric ColDis, analysts can interactively select different feature sets, refine fraud detection algorithms, tune parameters and evaluate the detection result in near real-time. We demonstrate the effectiveness and significance of FDHelper through two case studies with state-of-the-art fraud detection algorithms, interviews with domain experts and algorithm experts, and a user study with eight first-time end users.

Understanding Walking Meetings: Drivers and Barriers

There is increased interest in reducing sedentary behavior of office workers to combat the negative health effects of prolonged sitting. Walking meetings offer a promising solution to this problem as they facilitate a physically active way of working. To inform future development of technologies supporting these type of meetings, in-depth qualitative insights into people's experiences of walking meetings are needed. We conducted semi-structured walking interviews (N=16) to identify key drivers and barriers for walking meetings in a living lab setting by using the 'WorkWalk'. The 'WorkWalk' is a 1.8 km walking route indicated by a dotted blue line with outdoor meeting points, integrated into the room booking system. Our findings provide insights into how walking meetings are experienced and affect the set-up and social dynamics of meetings. We offer design recommendations for the development of future technologies and service design elements to support walking meetings and active ways of working.

Listen to Developers! A Participatory Design Study on Security Warnings for Cryptographic APIs

The positive effect of security information communicated to developers through API warnings has been established. However, current prototypical designs are based on security warnings for end-users. To improve security feedback for developers, we conducted a participatory design study with 25 professional software developers in focus groups. We identify which security information is considered helpful in avoiding insecure cryptographic API use during development. Concerning console messages, participants suggested five core elements, namely message classification, title message, code location, link to detailed external resources, and color. Design guidelines for end-user warnings are only partially suitable in this context. Participants emphasized the importance of tailoring the detail and content of security information to the context. Console warnings call for concise communication; further information needs to be linked externally. Therefore, security feedback should transcend tools and should be adjustable by software developers across development tools, considering the work context and developer needs.

ReCog: Supporting Blind People in Recognizing Personal Objects

We present ReCog, a mobile app that enables blind users to recognize objects by training a deep network with their own photos of such objects. This functionality is useful to differentiate personal objects, which cannot be recognized with pre-trained recognizers and may lack distinguishing tactile features. To ensure that the objects are well-framed in the captured photos, ReCog integrates a camera-aiming guidance that tracks target objects and instructs the user through verbal and sonification feedback to appropriately frame them.

We report a two-session study with 10 blind participants using ReCog for object training and recognition, with and without guidance. We show that ReCog enables blind users to train and recognize their personal objects, and that camera-aiming guidance helps novice users to increase their confidence, achieve better accuracy, and learn strategies to capture better photos.

Breaking The Experience: Effects of Questionnaires in VR User Studies

Questionnaires are among the most common research tools in virtual reality (VR) evaluations and user studies. However, transitioning from virtual worlds to the physical world to respond to VR experience questionnaires can potentially lead to systematic biases. Administering questionnaires in VR (inVRQs) is becoming more common in contemporary research. This is based on the intuitive notion that inVRQs may ease participation, reduce the Break in Presence (BIP) and avoid biases. In this paper, we perform a systematic investigation into the effects of interrupting the VR experience through questionnaires using physiological data as a continuous and objective measure of presence. In a user study (n=50), we evaluated question-asking procedures using a VR shooter with two different levels of immersion. The users rated their player experience with a questionnaire either inside or outside of VR. Our results indicate a reduced BIP for the employed inVRQ without affecting the self-reported player experience.

"Hey Model!" – Natural User Interactions and Agency in Accessible Interactive 3D Models

While developments in 3D printing have opened up opportunities for improved access to graphical information for people who are blind or have low vision (BLV), they can provide only limited detailed and contextual information. Interactive 3D printed models (I3Ms) that provide audio labels and/or a conversational agent interface potentially overcome this limitation. We conducted a Wizard-of-Oz exploratory study to uncover the multi-modal interaction techniques that BLV people would like to use when exploring I3Ms, and investigated their attitudes towards different levels of model agency. These findings informed the creation of an I3M prototype of the solar system. A second user study with this model revealed a hierarchy of interaction, with BLV users preferring tactile exploration, followed by touch gestures to trigger audio labels, and then natural language to fill in knowledge gaps and confirm understanding.

Meta-AR-App: An Authoring Platform for Collaborative Augmented Reality in STEM Classrooms

Augmented Reality (AR) has become a valuable tool for education and training processes. Meanwhile, cloud-based technologies can foster collaboration and other interaction modalities to enhance learning. We combine the cloud capabilities with AR technologies to present Meta-AR-App, an authoring platform for collaborative AR, which enables authoring between instructors and students. Additionally, we introduce a new application of an established collaboration process, the pull-based development model, to enable sharing and retrieving of AR learning content. We customize this model and create two modalities of interaction for the classroom: local (student to student) and global (instructor to class) pull. Based on observations from our user studies, we organize a four-category classroom model which implements our system: Work, Design, Collaboration, and Technology. Further, our system enables an iterative improvement workflow of the class content and enables synergistic collaboration that empowers students to be active agents in the learning process.

PenSight: Enhanced Interaction with a Pen-Top Camera

We propose mounting a downward-facing camera above the top end of a digital tablet pen. This creates a unique and practical viewing angle for capturing the pen-holding hand and the immediate surroundings which can include the other hand. The fabrication of a prototype device is described and the enabled interaction design space is explored, including dominant and non-dominant hand pose recognition, tablet grip detection, hand gestures, capturing physical content in the environment, and detecting users and pens. A deep learning computer vision pipeline is developed for classification, regression, and keypoint detection to enable these interactions. Example applications demonstrate usage scenarios and a qualitative user evaluation confirms the potential of the approach.

From Data to Insights: A Layered Storytelling Approach for Multimodal Learning Analytics

Significant progress to integrate and analyse multimodal data has been carried out in the last years. Yet, little research has tackled the challenge of visualising and supporting the sensemaking of multimodal data to inform teaching and learning. It is naïve to expect that simply by rendering multiple data streams visually, a teacher or learner will be able to make sense of them. This paper introduces an approach to unravel the complexity of multimodal data by organising it into meaningful layers that explain critical insights to teachers and students. The approach is illustrated through the design of two data storytelling prototypes in the context of nursing simulation. Two authentic studies with educators and students identified the potential of the approach to create learning analytics interfaces that communicate insights on team performance, as well as concerns in terms of accountability and automated insights discovery.

Computing Students' Learning Difficulties in HCI Education

Software developers often make interface design decisions and work with designers. Therefore, computing students who seek to become developers need some education about interface design. While prior work has studied difficulties that educators face when teaching design to computing students, there is comparatively little work on the difficulties computing students face when learning HCI design skills. To uncover these difficulties, we conducted two qualitative studies consisting of surveys and interviews with (1) computing students and (2) educators who teach interface design to computing students. Qualitative analysis of their responses revealed 18 types of learning difficulties students might experience in HCI design education, including difficulties around the mechanics of design work, project management skills, the wicked nature of design problems, and distorted perspectives on design.

Evaluating 'Prefer not to say' Around Sensitive Disclosures

As people's offline and online lives become increasingly entwined, the sensitivity of personal information disclosed online is increasing. Disclosures often occur through structured disclosure fields (e.g., drop-down lists). Prior research suggests these fields may limit privacy, with non-disclosing users being presumed to be hiding undesirable information. We investigated this around HIV status disclosure in online dating apps used by men who have sex with men. Our online study asked participants (N=183) to rate profiles where HIV status was either disclosed or undisclosed. We tested three designs for displaying undisclosed fields. Visibility of undisclosed fields had a significant effect on the way profiles were rated, and other profile information (e.g., ethnicity) could affect inferences that develop around undisclosed information. Our research highlights complexities around designing for non-disclosure and questions the voluntary nature of these fields. Further work is outlined to ensure disclosure control is appropriately implemented around online sensitive information disclosures.

Proximate Social Factors in First-Time Contribution to Online Communities

In the course of every member's integration into an online community, a decision must be made to participate for the first time. The challenges of effective recruitment, management, and retention of new users have been extensively explored in social computing research. However, little work has looked at in-the-moment factors that lead users to decide to participate instead of "lurk", conditions which can be shaped to draw new users in at crucial moments. In this work we analyze 183 million messages scraped from chatrooms on the livestreaming platform Twitch in order to understand differences between first-time participants' and regulars' behaviors and to identify conditions that encourage first-time participation. We find that presence of diverse types of users increases likelihood of new participation, with effects depending on the size of the community. We also find that information-seeking behaviors in first-time participation are negatively associated with retention in the short and medium term.

Data-driven Multi-level Segmentation of Image Editing Logs

Automatic segmentation of logs for creativity tools such as image editing systems could improve their usability and learnability by supporting such interaction use cases as smart history navigation or recommending alternative design choices. We propose a multi-level segmentation model that works for many image editing tasks including poster creation, portrait retouching, and special effect creation. The lowest-level chunks of logged events are computed using a support vector machine model and higher-level chunks are built on top of these, at a level of granularity that can be customized for specific use cases. Our model takes into account features derived from four event attributes collected in realistically complex Photoshop sessions with expert users: command, timestamp, image content, and artwork layer. We present a detailed analysis of the relevance of each feature and evaluate the model using both quantitative performance metrics and qualitative analysis of sample sessions.

Data Everyday: Data Literacy Practices in a Division I College Sports Context

Data analysis is central to sports training. Today, cutting-edge digital technologies are deployed to measure and improve athletes' performance. But too often researchers focus on the technology collecting performance data at the expense of understanding athletes' experiences with data. This is particularly the case in the understudied context of collegiate athletics, where competition is fierce, tools for data analysis abound, and the institution actively manages athletes' lives. By investigating how student-athletes analyze their performance data and are analyzed in turn, we can better understand the individual and institutional factors that make data literacy practices in athletics meaningful and productive-or not. Our pilot interview study of student-athletes at one Division I university reveals a set of opportunities for student-athletes to engage with and learn from data analytics practices. These opportunities come with a set of contextual tensions that should inform the design of new technologies for collegiate sports settings.

TalkingBoogie: Collaborative Mobile AAC System for Non-verbal Children with Developmental Disabilities and Their Caregivers

Augmentative and alternative communication (AAC) technologies are widely used to help non-verbal children enable communication. For AAC-aided communication to be successful, caregivers should support children with consistent intervention strategies in various settings. As such, caregivers need to continuously observe and discuss children's AAC usage to create a shared understanding of these strategies. However, caregivers often find it challenging to effectively collaborate with one another due to a lack of family involvement and the unstructured process of collaboration. To address these issues, we present TalkingBoogie, which consists of two mobile apps: TalkingBoogie-AAC for caregiver-child communication, and TalkingBoogie-coach supporting caregiver collaboration. Working together, these applications provide contextualized layouts for symbol arrangement, scaffold the process of sharing and discussing observations, and induce caregivers' balanced participation. A two-week deployment study with four groups (N=11) found that TalkingBoogie helped increase mutual understanding of strategies and encourage balanced participation between caregivers with reduced cognitive loads.

texSketch: Active Diagramming through Pen-and-Ink Annotations

Learning from text is a constructive activity in which sentence-level information is combined by the reader to build coherent mental models. With increasingly complex texts, forming a mental model becomes challenging due to a lack of background knowledge, and limits in working memory and attention. To address this, we are taught knowledge externalization strategies such as active reading and diagramming. Unfortunately, paper-and-pencil approaches may not always be appropriate, and software solutions create friction through difficult input modalities, limited workflow support, and barriers between reading and diagramming. For all but the simplest text, building coherent diagrams can be tedious and difficult. We propose Active Diagramming, an approach extending familiar active reading strategies to the task of diagram construction. Our prototype, texSketch, combines pen-and-ink interactions with natural language processing to reduce the cost of producing diagrams while maintaining the cognitive effort necessary for comprehension. Our user study finds that readers can effectively create diagrams without disrupting reading.

"Out of Luck": Socio-Economic Differences in Student Coping Responses to Technology Problems

Despite high levels of digital technology access among college students, technology disruption remains an issue. This study was conducted to understand how technology disruption might contribute to socio-economic disparities in academic performance. Data were analyzed from a non-representative sample of 748 undergraduate students. We examined socio-economic differences in types of technology problems students experience; the consequences of those problems; and beliefs about how to handle future problems. Socio-economic status was not associated with types of technology problems, but it was associated with greater negative consequences and less-efficacious beliefs about handling future situations. These findings are consistent with sociological work on socio-economic differences in student help-seeking. They also elaborate mechanistic understanding of the technology maintenance construct. Finally, for those interested in designing to reduce socio-economic inequalities, they suggest the need for interfaces that go beyond information accessibility to facilitate student empowerment and student-teacher communication.

Exploring Auditory Information to Change Users' Perception of Time Passing as Shorter

Although the processing speed of computers has been drastically increasing year by year, users still have to wait for computers to complete tasks or to respond. To cope with this, several studies have proposed presenting certain visual information to users to change their perception of time passing as shorter, e.g., progress bars with animated ribbing or faster/slower virtual clocks. As speech interfaces such as smart speakers are becoming popular, a novel method is required to make users perceive the passing of time as shorter by presenting auditory stimuli. We thus prepared 20 pieces of auditory information as experimental stimuli; that is, 11 auditory stimuli that have the same 10.1-second duration but different numbers of 0.1-second sine-wave sounds and 9 other auditory stimuli that have the same 10.1-second duration and numbers of sounds but different interval patterns between the sounds. We conducted three experiments to figure out which kinds of auditory stimuli can change users' perception of time passing as shorter. We found that a 10.1-second auditory stimulus that has 0.1-second sine-wave sounds appearing 11 times with intervals between the sounds that narrow rapidly in a linear fashion was perceived as shortest at about 9.3 seconds, which was 7.6% shorter than the actual duration of the stimulus. We also found that different interval patterns of sounds in auditory information significantly affected users' perception of time passing as shorter, while different numbers of sounds did not.

Place-Based Policymaking and HCI: Opportunities and Challenges for Technology Design

There has been a growing interest in HCI in designing and developing technology to support democratic participation, particularly in the domain of urban planning or place-based research. In addition, the HCI field has increasingly considered the intersection of HCI and policymaking to understand how our research can have a broader impact. In this paper, we report on a series of workshops with citizens and city planners to explore place-based policymaking through the case study of neighbourhood planning in the UK. Our analysis highlights the tensions, opportunities and challenges faced by citizens in creating policy. Drawing from our findings, we stress the need for HCI to be actively involved in supporting, innovating and (re)designing civic policymaking processes while emphasising design considerations for the development of technological tools.

Designing Clinical AAC Tablet Applications with Adults who have Mild Intellectual Disabilities

Patients with mild intellectual disabilities (ID) face significant communication barriers within primary care services. This has a detrimental effect on the quality of treatment being provided, meaning the consultation process could benefit from augmentative and alternative communication (AAC) technologies. However, little research has been conducted in this area beyond that of paper-based aids. We address this by extracting design requirements for a clinical AAC tablet application from n=10 adults with mild ID. Our results show that such technologies can promote communication between general practitioners (GPs) and patients with mild ID by extracting symptoms in advance of the consultation via an accessible questionnaire. These symptoms act as a referent and assist in raising the awareness of conditions commonly overlooked by GPs. Furthermore, the application can support people with ID in identifying and accessing healthcare services. Finally, the participants identified 6 key factors that affect the clarity of medical images.

Pronto: Rapid Augmented Reality Video Prototyping Using Sketches and Enaction

Designers have limited tools to prototype AR experiences rapidly. Can lightweight, immediate tools let designers prototype dynamic AR interactions while capturing the nuances of a 3D experience? We interviewed three AR experts and identified several recurring issues in AR design: creating and positioning 3D assets, handling the changing user position, and orchestrating multiple animations. We introduce PROJECT PRONTO, a tablet-based video prototyping system that combines 2D video with 3D manipulation. PRONTO supports four intertwined activities: capturing 3D spatial information alongside a video scenario, positioning and sketching 2D drawings in a 3D world, and enacting animations with physical interactions. An observational study with professional designers shows that participants can use PRONTO to prototype diverse AR experiences. All participants performed two tasks: replicating a sample non-trivial AR experience and prototyping their open-ended designs. All participants completed the replication task and found PRONTO easy to use. Most participants found that PRONTO encourages more exploration of designs than their current practices.

Student Engagement in Sensitive Design Contexts: A Case Study in Dementia Care

There is a growing body of HCI work that seeks to understand and enhance the lived experience of people with dementia. The majority of this work involves researchers working alongside people with dementia and their carers, focused on the design project outcomes. In order to enrich the social context of this work, we explore broadening participation to include student volunteers. To encourage mutually engaging experiences in this design context, careful consideration of how to support both students and people with dementia is needed. In this paper, we present two case- studies of co-design projects between students and people with dementia. Our findings detail the use of design methods to reconfigure the role of the residents in care contexts and the students learning process. We discuss the project learning outcomes as well as practical and ethical considerations to support the use of design methods to support mutual engagement in sensitive contexts.

Social Acceptability in HCI: A Survey of Methods, Measures, and Design Strategies

With the increasing ubiquity of personal devices, social acceptability of human-machine interactions has gained relevance and growing interest from the HCI community. Yet, there are no best practices or established methods for evaluating social acceptability. Design strategies for increasing social acceptability have been described and employed, but so far not been holistically appraised and evaluated. We offer a systematic literature analysis (N=69) of social acceptability in HCI and contribute a better understanding of current research practices, namely, methods employed, measures and design strategies. Our review identified an unbalanced distribution of study approaches, shortcomings in employed measures, and a lack of interweaving between empirical and artifact-creating approaches. The latter causes a discrepancy between design recommendations based on user research, and design strategies employed in artifact creation. Our survey lays the groundwork for a more nuanced evaluation of social acceptability, the development of best practices, and a future research agenda.

Does Smartphone Use Drive our Emotions or vice versa? A Causal Analysis

In this paper, we demonstrate the existence of a bidirectional causal relationship between smartphone application use and user emotions. In a two-week long in-the-wild study with 30 participants we captured 502,851 instances of smartphone application use in tandem with corresponding emotional data from facial expressions. Our analysis shows that while in most cases application use drives user emotions, multiple application categories exist for which the causal effect is in the opposite direction. Our findings shed light on the relationship between smartphone use and emotional states. We furthermore discuss the opportunities for research and practice that arise from our findings and their potential to support emotional well-being.

EAST: Early Autism Screening Tool for Preschoolers

We describe the iterative co-design process and evaluation of an early autism screening tool (EAST). EAST is an intermediary interactive tablet based app that assists in the early-detection of Autism Spectrum Disorder (ASD) by screening preschoolers in Pakistan through play-based activities in a home, school or clinical setting. Medical professionals, parents of autistic children and teachers were surveyed through focus groups to understand the reasons that contribute to the increasing number of missed early detections, and late- or misdiagnoses. We also evaluate the acceptability, usability and validity of our tool. We tested EAST with both typically developed and autistic children on how they relate to people, imitation, motor skills, visual and intellectual response. They were scored via time taken, the number of wrong attempts, or incorrect answers and audiovisual feedback. This paper contributes towards a digital autism screening tool that delivers insights into the child's behaviour and enables collaboration among parents, teachers and medical professionals.

Why Johnny Can't Unsubscribe: Barriers to Stopping Unwanted Email

A large proportion of email messages in an average Internet user's inbox are unwanted commercial messages from mailing lists, bots, and so on. Although such messages often include instructions to unsubscribe, people still struggle with stopping unwanted email. We investigated the user experience of unsubscribing from unwanted email messages by recruiting 18 individuals for via a lab study followed by semi-structured interviews. Based on unsubscribing practices of the study participants, we synthesized eight common unsubscription mechanisms and identified the corresponding user experience challenges. We further uncovered alternative practices aimed at circumventing the need to unsubscribe. Our findings reveal frustration with the prevailing options for limiting access to the self by managing email boundaries. We apply our insight to offer design suggestions that could help commercial providers improve the user experience of unsubscribing and provide users more control over the email they receive.

Making Chat at Home in the Hospital: Exploring Chat Use by Nurses

In this paper, we examine WhatsApp use by nurses in India. Globally, personal chat apps have taken the workplace by storm, and healthcare is no exception. In the hospital setting, this raises questions around how chat apps are integrated into hospital work and the consequences of using such personal tools for work. To address these questions, we conducted an ethnographic study of chat use in nurses' work in a large multi-specialty hospital. By examining how chat is embedded in the hospital, rather than focusing on individual use of personal tools, we throw new light on the adoption of personal tools at work — specifically what happens when such tools are adopted and used as though they were organisational tools. In doing so, we explicate their impact on invisible work [77] and the creep of work into personal time, as well as how hierarchy and power play out in technology use. Thus, we point to the importance of looking beyond individual adoption by knowledge workers when studying the impact of personal tools at work.

The Politics of Privacy Theories: Moving from Norms to Vulnerabilities

Privacy and surveillance are central features of public discourse around use of computing systems. As the systems we design and study are increasingly used and regulated as potential instruments of surveillance, HCI researchers-even those whose focus is not privacy-find themselves needing to understand privacy in their work. Concepts like contextual integrity and boundary regulation have become touchstones for thinking about privacy in HCI. In this paper, we draw on HCI and privacy literature to understand the limitations of commonly used theories and examine their assumptions, politics, strengths, and weaknesses. We use a case study from the HCI literature to illustrate conceptual gaps in existing frameworks where privacy requirements can fall through. Finally, we advocate vulnerability as a core concept for privacy theorizing and examine how feminist, queer-Marxist, and intersectional thinking may augment our existing repertoire of privacy theories to create a more inclusive scholarship and design practice.

What is this URL's Destination? Empirical Evaluation of Users' URL Reading

Common anti-phishing advice tells users to mouse over links, look at the URL, and compare to the expected destination, implicitly assuming that they are able to read the URL. To test this assumption, we conducted a survey with 1929 participants recruited from the Amazon Mechanical Turk and Prolific Academic platforms. Participants were shown 23 URLs with various URL structures. For each URL, participants were asked via a multiple choice question where the URL would lead and how safe they feel clicking on it would be. Using latent class analysis, participants were stratified by self-reported technology use. Participants were strongly biased towards answering that the URL would lead to the website of the organization whose name appeared in the URL, regardless of its position in the URL structure. The group with the highest technology use was only minorly better at URL reading.

"Arseing around was Fun!" – Humor as a Resource in Design and Making

Humor is an inevitable part of human life. Most of us are capable of experiencing and appreciating humor. From this perspective, surprisingly little HCI research can be found scrutinizing the existence, role, and potential of humor in our design practice. The gap remains also related to children and teenagers; there is a lack of studies appreciating the emergence and existence of humor in the design process without intentionally evoking it. Thus, this study examines humor as a naturally occurring phenomenon in the design process. The study was conducted in collaboration with a class of teenagers and their teachers. The study identifies various forms and functions of humor in the design process and reveals its situated, emergent nature as a resource in interaction within design. The study proposes a practical tool for designers for anticipating and potentially facilitating the emergence, forms and usages of humor as an interactional resource in design.

Understanding the Care Ecologies of Veterans with PTSD

Post-traumatic stress disorder (PTSD) disproportionately affects United States veterans, yet they may be reluctant to seek or engage in care. We interview 21 participants, including veterans with PTSD, clinicians who treat veterans and friends and family that support veterans through mental health ordeals. We investigate the military identity these veterans share. We explore how this may add to their reluctance in care-seeking behaviors. We also explore the roles of human and non-human intermediaries in ecologies of care and the potential for enhancing patient empowerment in current clinical treatment contexts. We discuss how military culture can be utilized in clinical care, how multiple perspectives can be leveraged to create a more holistic view of the patient, and finally, how veterans can be empowered during treatment. We conclude with recommendations for the design of sociotechnical systems that prioritize the above in support of the mental well-being of veterans with PTSD.

Self-Expression by Design: Co-Designing the ExpressiBall with Minimally-Verbal Children on the Autism Spectrum

Expressing one's thoughts and feelings is a fundamental human need - the basis for communication and social interaction. We ask, how do minimally-verbal children on the autism spectrum express themselves? How can we better recognise instances of self-expression? And how might technologies support and encourage self-expression? To address these questions, we undertook co-design research at an autism-specific primary school with 20 children over one school year. This paper contributes six Modalities of Self-Expression, through which children self-express and convey their design insights. Each modality of self-expression can occur across two different dimensions (socio-expressive and auto-expressive) and can be of a fundamental or an integrative nature. Further, we contribute the design trajectory of a tangible ball prototype, the ExpressiBall, which - through voice, sounds, lights, and motion sensors - explores how tangible technologies can support this range of expressive modalities. Finally, we discuss the concept of Self-Expression by Design.

DataQuilt: Extracting Visual Elements from Images to Craft Pictorial Visualizations

Recent years have seen an increasing interest in the authoring and crafting of personal visualizations. Mainstream data analysis and authoring tools lack the flexibility for customization and personalization, whereas tools from the research community either require creativity and drawing skills, or are limited to simple vector graphics. We present DataQuilt, a novel system that enables visualization authors to iteratively design pictorial visualizations as collages. Real images (e.g., paintings, photographs, sketches) act as both inspiration and as a resource of visual elements that can be mapped to data. The creative pipeline involves the semi-guided extraction of relevant elements of an image (arbitrary regions, regular shapes, color palettes, textures) aided by computer vision techniques; the binding of these graphical elements and their features to data in order to create meaningful visualizations; and the iterative refinement of both features and visualizations through direct manipulation. We demonstrate the usability of DataQuilt in a controlled study and its expressiveness through a collection of authored visualizations from a second open-ended study.

EYEditor: Towards On-the-Go Heads-Up Text Editing Using Voice and Manual Input

On-the-go text-editing is difficult, yet frequently done in everyday lives. Using smartphones for editing text forces users into a heads-down posture which can be undesirable and unsafe. We present EYEditor, a heads-up smartglass-based solution that displays the text on a see-through peripheral display and allows text-editing with voice and manual input. The choices of output modality (visual and/or audio) and content presentation were made after a controlled experiment, which showed that sentence-by-sentence visual-only presentation is best for optimizing users' editing and path-navigation capabilities. A second experiment formally evaluated EYEditor against the standard smartphone-based solution for tasks with varied editing complexities and navigation difficulties. The results showed that EYEditor outperformed smartphones as either the path OR the task became more difficult. Yet, the advantage of EYEditor became less salient when both the editing and navigation was difficult. We discuss trade-offs and insights gained for future heads-up text-editing solutions.

"No powers, man!": A Student Perspective on Designing University Smart Building Interactions

Smart buildings offer an opportunity for better performance and enhanced experience by contextualising services and interactions to the needs and practices of occupants. Yet, this vision is limited by established approaches to building management, delivered top-down through professional facilities management teams, opening up an interaction-gap between occupants and the spaces they inhabit. To address the challenge of how smart buildings might be more inclusively managed, we present the results of a qualitative study with student occupants of a smart building, with design workshops including building walks and speculative futuring. We develop new understandings of how student occupants conceptualise and evaluate spaces as they experience them, and of how building management practices might evolve with new sociotechnical systems that better leverage occupant agency. Our findings point to important directions for HCI research in this nascent area, including the need for HBI (Human-Building Interaction) design to challenge entrenched roles in building management.

"I Hear You, I Feel You": Encouraging Deep Self-disclosure through a Chatbot

Chatbots have great potential to serve as a low-cost, effective tool to support people's self-disclosure. Prior work has shown that reciprocity occurs in human-machine dialog; however, whether reciprocity can be leveraged to promote and sustain deep self-disclosure over time has not been systematically studied. In this work, we design, implement and evaluate a chatbot that has self-disclosure features when it performs small talk with people. We ran a study with 47 participants and divided them into three groups to use different chatting styles of the chatbot for three weeks. We found that chatbot self-disclosure had a reciprocal effect on promoting deeper participant self-disclosure that lasted over the study period, in which the other chat styles without self-disclosure features failed to deliver. Chatbot self-disclosure also had a positive effect on improving participants' perceived intimacy and enjoyment over the study period. Finally, we reflect on the design implications of chatbots where deep self-disclosure is needed over time.

CARoma Therapy: Pleasant Scents Promote Safer Driving, Better Mood, and Improved Well-Being in Angry Drivers

Driving is a task that is often affected by emotions. The effect of emotions on driving has been extensively studied. Anger is an emotion that dominates in such investigations. Despite the knowledge on strong links between scents and emotions, few studies have explored the effect of olfactory stimulation in a context of driving. Such an outcome provides HCI practitioners very little knowledge on how to design for emotions using olfactory stimulation in the car. We carried out three studies to select scents of different valence and arousal levels (i.e. rose, peppermint, and civet) and anger eliciting stimuli (i.e. affective pictures and on-road events). We used this knowledge to conduct the fourth user study investigating how the selected scents change the emotional state, well-being, and driving behaviour of drivers in an induced angry state. Our findings enable better decisions on what scents to choose when designing interactions for angry drivers.

Understanding and Visualizing Data Iteration in Machine Learning

Successful machine learning (ML) applications require iterations on both modeling and the underlying data. While prior visualization tools for ML primarily focus on modeling, our interviews with 23 ML practitioners reveal that they improve model performance frequently by iterating on their data (e.g., collecting new data, adding labels) rather than their models. We also identify common types of data iterations and associated analysis tasks and challenges. To help attribute data iterations to model performance, we design a collection of interactive visualizations and integrate them into a prototype, Chameleon, that lets users compare data features, training/testing splits, and performance across data versions. We present two case studies where developers apply \system to their own evolving datasets on production ML projects. Our interface helps them verify data collection efforts, find failure cases stretching across data versions, capture data processing changes that impacted performance, and identify opportunities for future data iterations.

Is This An Ad?: Automatically Disclosing Online Endorsements On YouTube With AdIntuition

Undisclosed online endorsements on social media can be misleading to users who may not know when viewed content contains advertisements. Despite federal regulations requiring content creators to disclose online endorsements, studies suggest that less than 10% do so in practice. To overcome this issue, we need knowledge of how to best detect online endorsements, knowledge about how prevalent online endorsements are in the wild, and ways to design systems to automatically disclose advertising content to viewers. To that end, we designed, implemented, and evaluated a tool called AdIntuition which automatically discloses when YouTube videos contain affiliate marketing, a type of social media endorsement. We evaluated AdIntuition with 783 users using a survey, field deployment, and diary study. We discuss our findings and recommendations for future measurements of and tools to detect and alert users about affiliate marketing content.

Unplatformed Design: A Model for Appropriating Social Media Technologies for Coordinated Participation

Using existing social media technologies as a resource for design offers significant potential for sustainable and scalable ways of coordinating participation. We look at three exemplar projects in three distinct domains that have successfully coordinated participation through the configuration and augmentation of existing social media technologies: participatory future forecasting, participatory health research, and connectivist learning. In this paper we conceptualise social media technologies as material for design, that is, as the raw material with which coordinated participation is realized. From this we develop a model that proposes four material qualities of social media technologies, morphology, role, representation of activity and permeability, and point to how they can be productively employed in the design of coordination of participation.

DoughNets: Visualising Networks Using Torus Wrapping

We investigate visualisations of networks on a 2-dimensional torus topology, like an opened-up and flattened doughnut. That is, the network is drawn on a rectangular area while "wrapping" specific links around the border. Previous work on torus drawings of networks has been mostly theoretical, limited to certain classes of networks, and not evaluated by human readability studies. We offer a simple interactive layout approach applicable to general graphs. We use this to find layouts affording better aesthetics in terms of conventional measures like more equal edge length and fewer crossings. In two controlled user studies we find that torus layout with either additional context or interactive panning provided significant performance improvement (in terms of error and time) over torus layout without either of these improvements, to the point that it is comparable to standard non-torus layout.

Addressing Cognitive and Emotional Barriers in Parent-Clinician Communication through Behavioral Visualization Webtools

Effective communication between clinicians and parents of young children with developmental delays can decrease parents' anxiety, help them handle bad news, and improve their adherence to proposed interventions. However, parents have reported dissatisfaction regarding their current communication with clinicians, and they face cognitive and emotional challenges when discussing their child's developmental delays. In this paper, we present visualization as a facilitator of parent-clinician communication and how it could address existing communication challenges. Parents and clinicians anticipated visualization webtools would aid their communication by helping parents gain a better understanding of their child, acting as objective evidence, and highlighting the strength of the child as well as important medical concepts. In addition, visualization can act as a longitudinal record, helping parents track, explore, and share their child's developmental progress. Finally, we propose visualization as a tool to guide parents in their transition from feeling emotional and disempowered to advocating with confidence.

"On Finsta, I can say 'Hail Satan'": Being Authentic but Disagreeable on Instagram

We use personality theory to compare self-presentation between multiple Instagram accounts, investigating authenticity and consistency. Many studies claim social media promote inauthentic self-presentation focused on socially desirable traits. At the same time, affordances suggest that self-presentation should be relatively consistent within one social medium. For 88 participants, we examine personality traits for 'real Instagram' ('Rinsta') versus 'fake Instagram' ('Finsta') accounts, comparing these with people's offline traits using mixed-methods. Counterintuitively, we find Finsta accounts often present socially undesirable traits. Furthermore, different accounts on the same social medium reveal quite different styles of self-presentation. Overall Finstas are more Extraverted, less Conscientious, and less Agreeable than Rinstas, although equally Neurotic as offline. Interviews indicate trait differences arise from differing audience perceptions. A large anonymous Rinsta audience promotes a carefully curated self. In contrast, a small but trusted Finsta audience can engender more authentic, but negative self-presentation. We discuss design and theory implications.

Inhaling and Exhaling: How Technologies Can Perceptually Extend our Breath Awareness

Attending to breath is a self-awareness practice that exists within many contemplative and reflective traditions and is recognized for its benefits to well-being. Our current technological landscape embraces a large body of systems that utilize breath data in order to foster self-awareness. This paper seeks to deepen our understanding of the design space of systems that perceptually extend breath awareness. Our contribution is twofold: (1) our analysis reveals how the underlying theoretical frameworks shape the system design and its evaluation, and (2) how system design features support perceptual extension of breath awareness. We review and critically analyze 31 breath-based interactive systems. We identify 4 theoretical frameworks and 3 design strategies for interactive systems that perceptually extend breath awareness. We reflect upon this design space from both a theoretical and system design perspective, and propose future design directions for developing systems that "listen to" breath and perceptually extend it.

Reading with the Tongue: Individual Differences Affect the Perception of Ambiguous Stimuli with the BrainPort

There is an increasing interest in non-visual interfaces for HCI to take advantage of the information processing capability of the other sensory modalities. The BrainPort is a vision-to-tactile sensory substitution device that conveys information through electro-stimulation on the tongue. As the tongue is a horizontal surface, it makes for an interesting platform to study the brain's representation of space. But which way is up on the tongue? We provided participants with perceptually ambiguous stimuli and measured how often different perspectives were adopted; furthermore, whether camera orientation and gender had an effect. Additionally, we examined whether personality (trait extraversion and openness) could predict the perspective taken. We found that self-centered perspectives were predominantly adopted, and that trait openness may predict perspective. This research demonstrates how individual differences can affect the usability of sensory substitution devices, and highlights the need for flexible and customisable interfaces.

Bottom-Up Organizing with Tools from On High: Understanding the Data Practices of Labor Organizers

This paper provides insight into the use of data tools in the American labor movement by analyzing the practices of staff employed by unions to organize alongside union members. We interviewed 23 field-level staff organizers about how they use data tools to evaluate membership. We find that organizers work around and outside of these tools to develop access to data for union members and calibrate data representations to meet local needs. Organizers mediate between local and central versions of the data, and draw on their contextual knowledge to challenge campaign strategy. We argue that networked data tools can compound field organizers' lack of discretion, making it more difficult for unions to assess and act on the will of union membership. We show how the use of networked data tools can lead to less accurate data, and discuss how bottom-up approaches to data gathering can support more accurate membership assessments.

Move Your Body: Engaging Museum Visitors with Human-Data Interaction

Museums have embraced embodied interaction: its novelty generates buzz and excitement among their patrons, and it has enormous educational potential. Human-Data Interaction (HDI) is a class of embodied interactions that enables people to explore large sets of data using interactive visualizations that users control with gestures and body movements. In museums, however, HDI installations have no utility if visitors do not engage with them. In this paper, we present a quasi-experimental study that investigates how different ways of representing the user ("mode type") next-to a data visualization alters the way in which people engage with a HDI system. We consider four mode types: avatar, skeleton, camera overlay, and control. Our findings indicate that the mode type impacts the number of visitors that interact with the installation, the gestures that people do, and the amount of time that visitors spend observing the data on display and interacting with the system.

Experiential Qualities of Whispering with Voice Assistants

We present a Research through Design project that explores how whispering influences the ways people experience and interact with voice assistants. The research project includes a co-speculation workshop and the use of a design probe, which culminated in the production of a design fiction short film. Our design-led inquiry contributes with experiential qualities of whispering with voice assistants: creepiness, trust, and intimacy. Furthermore, we present how whispering opens up new dimensions of how and when voice interaction could be used. We propose that designers of whispering voice assistants should reflect on how they facilitate the experiential qualities of creepiness, trust, and intimacy, and reflect on the potential challenges whispering brings to the relation between a user and a voice assistant.

Tricks and Treats: Designing Technology to Support Mobility Assistance Dogs

Assistance dogs are a key intervention to support the autonomy of people with tetraplegia. Previous research on assistive technologies have investigated ways to, ultimately, replace their labour using technology, for instance through the design of smart home environments. However, both the disability studies literature and our interviews suggest there is an immediate need to support these relationships, both in terms of training and bonding. Through a case study of an accessible dog treats dispenser, we investigate a technological intervention responding to these needs, detailing an appropriate design methodology and contributing insights into user requirements and preferences.

3D-Auth: Two-Factor Authentication with Personalized 3D-Printed Items

Two-factor authentication is a widely recommended security mechanism and already offered for different services. However, known methods and physical realizations exhibit considerable usability and customization issues. In this paper, we propose 3D-Auth, a new concept of two-factor authentication. 3D-Auth is based on customizable 3D-printed items that combine two authentication factors in one object. The object bottom contains a uniform grid of conductive dots that are connected to a unique embedded structure inside the item. Based on the interaction with the item, different dots turn into touch-points and form an authentication pattern. This pattern can be recognized by a capacitive touchscreen. Based on an expert design study, we present an interaction space with six categories of possible authentication interactions. In a user study, we demonstrate the feasibility of 3D-Auth items and show that the items are easy to use and the interactions are easy to remember.

HapBead: On-Skin Microfluidic Haptic Interface using Tunable Bead

On-skin haptic interfaces using soft elastomers which are thin and flexible have significantly improved in recent years. Many are focused on vibrotactile feedback that requires complicated parameter tuning. Another approach is based on mechanical forces created via piezoelectric devices and other methods for non-vibratory haptic sensations like stretching, twisting. These are often bulky with electronic components and associated drivers are complicated with limited control of timing and precision. This paper proposes HapBead, a new on-skin haptic interface that is capable of rendering vibration like tactile feedback using microfluidics. HapBead leverages a microfluidic channel to precisely and agilely oscillate a small bead via liquid flow, which then generates various motion patterns in channel that creates highly tunable haptic sensations on skin. We developed a proof-of-concept design to implement thin, flexible and easily affordable HapBead platform, and verified its haptic rendering capabilities via attaching it to users' fingertips. A study was carried out and confirmed that participants could accurately tell six different haptic patterns rendered by HapBead. HapBead enables new wearable display applications with multiple integrated functionalities such as on-skin haptic doodles, visuo-haptic displays and haptic illusions.

See No Evil, Hear No Evil, Speak No Evil: How Collegiate Players Define, Experience and Cope with Toxicity

Toxicity in online environments is a complex and a systemic issue. Collegiate esports communities seem to be particularly vulnerable to toxic behaviors. In esports games, negative behavior, such as harassment, can create barriers to players achieving high performance and can reduce enjoyment which may cause them to leave the game. The aim of this study is to investigate how players define, experience and deal with toxicity in esports games that they play. Our findings from an interview study and five monthly follow ups with 19 participants from a university esports club show that players define toxicity as behaviors disrupt their morale and team dynamics, and are inclined to normalize negative behaviors, rationalize it as part of the competitive game culture akin to traditional sports, and participate a form of gamer classism, believing that toxicity is more common in lower level play than in professional and collegiate esports. There are many coping mechanisms employed by collegiate esports players, including ignoring offenders, deescalating tense encounters, and using tools to mute offenders. Understanding the motivations behind collegiate esports players' engagement with toxicity may help the growing sport plot a positive trajectory towards healthy play.

Live Sketchnoting Across Platforms: Exploring the Potential and Limitations of Analogue and Digital Tools

Sketchnoting is the process of creating a visual record with combined text and imagery of an event or presentation. Although analogue tools are still the most common method for sketchnoting, the use of digital tools is increasing. We conducted a study to better understand the current practices, techniques, compromises and opportunities of creating both pen&paper and digital sketchnotes. Our research combines insights from semi-structured interviews with the findings from a within-subjects observational study where ten participants created real time sketchnotes of two video presentations on both paper and digital tablet. We report our key findings, categorised into six themes: insights into sense of space; trade-offs with flexibility; choice paradox and cognitive load; matters of perception, accuracy and texture; issues around confidence; and practicalities. We discuss those findings, the potential and limitations of different methods, and implications for the design of future digital sketchnoting tools.

Power Play: How the Need to Empower or Overpower Other Players Predicts Preferences in League of Legends

The power motive describes our need to have an impact on others. Relevant in contexts such as sports, politics, and business, the power motive could help explain experiences and behaviours in digital games. We present four studies connecting the power motive to role and champion type choices in the MOBA game League of Legends (LoL). In Study1 we demonstrate that overall power motive does not predict role preferences. In Study2 we develop a 6-item-scale distinguishing between two facets of power in game settings: prosociality (empowering others) and dominance (overpowering others). In Study3 we show that prosociality and dominance uniquely predict role preferences for Support and Top Lane. In Study4 we demonstrate that champion type choice (tank, fighter, slayer, controller) is uniquely predicted by dominance and prosociality. We provide insight on how the wish for vertical interactions with other players-the power motive-can influence player interactions in multiplayer games.

Dynamics of Aimed Mid-air Movements

Mid-air arm movements are ubiquitous in VR, AR, and gestural interfaces. While mouse movements have received some attention, the dynamics of mid-air movements are understudied in HCI. In this paper we present an exploratory analysis of the dynamics of aimed mid-air movements. We explore the 3rd order lag (3OL) and existing 2nd order lag (2OL) models for modeling these dynamics. For a majority of movements the 3OL model captures mid-air dynamics better, in particular acceleration. The models can effectively predict the complete time series of position, velocity and acceleration of aimed movements given an initial state and a target using three (2OL) or four (3OL) free parameters.

Therminator: Understanding the Interdependency of Visual and On-Body Thermal Feedback in Virtual Reality

Recent advances have made Virtual Reality (VR) more realistic than ever before. This improved realism is attributed to today's ability to increasingly appeal to human sensations, such as visual, auditory or tactile. While research also examines temperature sensation as an important aspect, the interdependency of visual and thermal perception in VR is still underexplored. In this paper, we propose Therminator, a thermal display concept that provides warm and cold on-body feedback in VR through heat conduction of flowing liquids with different temperatures. Further, we systematically evaluate the interdependency of different visual and thermal stimuli on the temperature perception of arm and abdomen with 25 participants. As part of the results, we found varying temperature perception depending on the stimuli, as well as increasing involvement of users during conditions with matching stimuli.

Multimodal Gaze Interaction for Creative Design

We present a new application ("Sakura") that enables people with physical impairments to produce creative visual design work using a multimodal gaze approach. The system integrates multiple features tailored for gaze interaction including the selection of design artefacts via a novel grid approach, control methods for manipulating canvas objects, creative typography, a new color selection approach, and a customizable guide technique facilitating the alignment of design elements. A user evaluation (N=24) found that non-disabled users were able to utilize the application to complete common design activities and that they rated the system positively in terms of usability. A follow-up study with physically impaired participants (N=6) demonstrated they were able to control the system when working towards a website design, rating the application as having a good level of usability. Our research highlights new directions in making creative activities more accessible for people with physical impairments.

The Effects of Explicit Intention Communication, Conspicuous Sensors, and Pedestrian Attitude in Interactions with Automated Vehicles

In this paper, we investigate the effect of an external human-machine interface (eHMI) and a conspicuous external vehicle appearance due to visible sensors on pedestrian interactions with automated vehicles (AVs). Recent research shows that AVs may need to explicitly communicate with the environment due to the absence of a driver. Furthermore, in interaction situations, an AV that looks different and conspicuous owing to an extensive sensor system may potentially lead to hesitation stemming from mistrust in automation. Thus, we evaluated in a virtual reality study how pedestrian attitude, the presence/absence of an eHMI, and a conspicuous sensor system affect their willingness to cross the road. Results recommend the use of an eHMI. A conspicuous appearance of automated-driving capability had no effect for the sample as a whole, although it led to more efficient crossing decisions for those with a more negative attitude towards AVs. Our findings contribute towards the effective design of future AV interfaces.

WATouCH: Enabling Direct Input on Non-touchscreen Using Smartwatch's Photoplethysmogram and IMU Sensor Fusion

Interacting with non-touchscreens such as TV or public displays can be difficult and inefficient. We propose WATouCH, a novel method that localizes a smartwatch on a display and allows direct input by turning the smartwatch into a tangible controller. This low-cost solution leverages sensor fusion of the built-in inertial measurement unit (IMU) and photoplethysmogram (PPG) sensor on a smartwatch that is used for heart rate monitoring. Specifically, WATouCH tracks the smartwatch movement using IMU data and corrects its location error caused by drift using the PPG responses to a dynamic visual pattern on the display. We conducted a user study on two tasks -- a point and click and line tracing task -- to evaluate the system usability and user performance. Evaluation results suggested that our sensor fusion mechanism effectively confined IMU-based localization error, achieved encouraging targeting and tracing precision, was well received by the participants, and thus opens up new opportunities for interaction.

Watch+Strap: Extending Smartwatches with Interactive StrapDisplays

While smartwatches are widely adopted these days, their input and output space remains fairly limited by their screen size. We present StrapDisplays-interactive watchbands with embedded display and touch technologies-that enhance commodity watches and extend their input and output capabilities. After introducing the physical design space of these StrapDisplays, we explore how to combine a smartwatch and straps in a synergistic Watch+Strap system. Specifically, we propose multiple interface concepts that consider promising content distributions, interaction techniques, usage types, and display roles. For example, the straps can enrich watch apps, display visualizations, provide glanceable feedback, or help avoiding occlusion issues. Further, we provide a modular research platform incorporating three StrapDisplay prototypes and a flexible web-based software architecture, demonstrating the feasibility of our approach. Early brainstorming sessions with 15 participants informed our design process, while later interviews with six experts supported our concepts and provided valuable feedback for future developments.

High Tempo Work: Design Challenges for Head-worn Displays in Quick Service Restaurants

Quick service restaurants (QSRs) are high tempo work environments that require collaboration and communication between crew. In a number of respects, head-worn displays (HWDs) might seem a promising technology to support QSR crew, but on close inspection they raise challenging issues for design. We conducted fieldwork studies at two large QSRs to understand how work is organised, how existing systems are used, and how information is displayed to and communicated between crew. We observed the crew working both routinely and with improvisation, collaboratively and individually, physically and digitally. From our analysis of the field study, we identify tentative use cases for HWDs, but with these also design tensions-that is, opportunities coupled with challenges that appear difficult to circumvent even with modest design proposals. These tensions would require careful consideration if HWDs were to be deployed in in QSRs, given that HWDs are ubiquitous, potentially private, digital, mobile, and able to collect behavioural data.

User's Role in Platform Infrastructuralization: WeChat as an Exemplar

Recent years have witnessed the rise of platforms such as Facebook and Google. Gigantic in scope and becoming omnipresent, these platforms are acquiring qualities of infrastructure, which is large-scale connected systems that support people's activities invisibly. Recent scholarship has identified WeChat, the most popular mobile social platform in China, as infrastructure. WeChat follows a platform logic to expand, and by conforming to the Chinese government's techno-nationalist focus, it has gradually become an infrastructure in China. We contribute to the understanding of platform infrastructuralization by taking WeChat as a case, highlighting the user's role in this process. We find user contributes to WeChat's infrastructuralization through a three-level interaction process: to practice, to appropriate, and to create. By calling out the user's role in platform infra-structuralization, we discuss how the CHI community can contribute to a better understanding of this phenomenon.

G-ID: Identifying 3D Prints Using Slicing Parameters

We present G-ID, a method that utilizes the subtle patterns left by the 3D printing process to distinguish and identify objects that otherwise look similar to the human eye. The key idea is to mark different instances of a 3D model by varying slicing parameters that do not change the model geometry but can be detected as machine-readable differences in the print. As a result, G-ID does not add anything to the object but exploits the patterns appearing as a by-product of slicing, an essential step of the 3D printing pipeline.

We introduce the G-ID slicing and labeling interface that varies the settings for each instance, and the G-ID mobile app, which uses image processing techniques to retrieve the parameters and their associated labels from a photo of the 3D printed object. Finally, we evaluate our method's accuracy under different lighting conditions, when objects were printed with different filaments and printers, and with pictures taken from various positions and angles.

Chase Lights in the Peripheral View: How the Design of Moving Patterns on an LED Strip Influences the Perception of Speed in an Automotive Context

LEDs on a strip, when turned on and off in a specific order, result in the perception of apparent motion (i.e. beta movement). In the automotive domain such chase lights have been used to alter drivers' perception of driving speed by manipulating the pixel speed of LEDs. We argue that the perceived velocity of beta movement in the peripheral view is not only based on the actual pixel speed but can be influenced by other factors such as frequency, width and brightness of lit LED segments. We conducted a velocity matching experiment (N=25) by systematically varying these three properties, in order to determine their influence on a participant's perceived velocity in a vehicle mock-up. Results show that a higher frequency and stronger brightness increased perceived velocity, whereas segment width had no influence. We discuss how findings may be applied when designing systems that use beta movement to influence the perception of ambient light velocity.

Morphic: Auto-Personalization on a Global Scale

Users frequently have trouble finding and changing technology settings, even when adjusting those settings to personalize their technology devices may significantly improve their user experience. This paper describes the Morphic project, a cloud-based auto-personalization tool. Primarily designed for improving accessibility, the auto-personalization in Morphic may also help a broader audience. This paper describes: 1) the technical infrastructure needed to support cloud-based auto-personalization, 2) the interaction design approaches necessary to support users during the personalization of their settings, and 3) which settings and modifications have been most frequently used. This paper presents the evolution of the Morphic project, the building of the infrastructure, the formative evaluation of various interaction design approaches (NFC cards, physical keypads, on-screen buttons, and menus), and implications for researchers and developers. It also includes preliminary findings from six technology probes.

Clinical Documentation as End-User Programming

As healthcare providers have transitioned from paper to electronic health records they have gained access to increasingly sophisticated documentation aids such as custom note templates. However, little is known about how providers use these aids. To address this gap, we examine how 48 ophthalmologists and their staff create and use content-importing phrases — a customizable and composable form of note template — to document office visits across two years. In this case study, we find 1) content-importing phrases were used to document the vast majority of visits (95%), 2) most content imported by these phrases was structured data imported by data-links rather than boilerplate text, and 3) providers primarily used phrases they had created while staff largely used phrases created by other people. We conclude by discussing how framing clinical documentation as end-user programming can inform the design of electronic health records and other documentation systems mixing data and narrative text.

Meeting Designers Where They Are: Using Industry Events as a Research Venue for HCI and Design Methods Development

There is much work in the CHI community about the 'industry-academia divide', and how to bridge it. One key crossover between HCI/UX scientists and practitioners is the development and use of tools and methods-boundary objects between academia and practice. Among other forms of collaboration, there is an underdeveloped opportunity for academics to make use of industry events (conferences, meetups, design jams) as a research venue in the context of tool and method development. This paper describes three cases from work in academia-industry engagement over the last decade, in which workshops or experiments have been run at industry events as a way of trialling and developing tools directly with practitioners. We discuss advantages of this approach and extract key insights and practical implications, highlighting how the CHI community might use this method more widely, gathering relevant research outcomes while contributing to knowledge exchange between academia and practice.

2Across: A Comparison of Audio-Tactile and Screen-Reader based Representations of a Crossword Puzzle

Crosswords are a popular recreational game that relies on the spatial relationship between words. As a player answers clues, they begin to organize words to form an intersecting grid. A good non-visual representation should convey the interrelation of words and support the user in building a practical spatial image of the crossword grid. This paper looks at two approaches to representing a crossword puzzle for visually impaired users: a screen reader based crossword, and an audio-tactile crossword puzzle. We evaluate the designs in a study with 10 visually impaired participants. The audio-tactile representation was found to support the practical use of the crossword's spatial structure while the screen reader based puzzle leveraged participant's prior experience in navigating websites. The paper discusses critical aspects of our study and presents a perspective on the use of multimodal interfaces for such spatial applications.

Utilizing Participant Voice in Volunteer Training

Delivering training to volunteers is a huge challenge for non-governmental organisations (NGOs). Traditional classroom-based approaches that dominate training are problematic due to the limited participation they offer to trainees. Peer-led approaches however, have shown promise in helping NGOs utilise trainee experiences within training. Although technologies are playing an increasing role in training, their benefits are not well understood. We describe our experience of designing peer-led training for community volunteers in rural India. Working alongside an NGO involved in community regeneration and social action, we collaboratively delivered a ten-day training workshop, deploying audio technologies to engage the participants in sharing lived experiences. We draw on reflections from trainers and trainees on how utilising participant voice can enhance training. We highlight opportunities around the usage of audio technologies for engaging with participant voice, including the ability to reclaim trainee agency within training and to work within cultural barriers.

A Conversation Analysis of Non-Progress and Coping Strategies with a Banking Task-Oriented Chatbot

Task-oriented chatbots are becoming popular alternatives for fulfilling users' needs, but few studies have investigated how users cope with conversational 'non-progress' (NP) in their daily lives. Accordingly, we analyzed a three-month conversation log between 1,685 users and a task-oriented banking chatbot. In this data, we observed 12 types of conversational NP; five types of content that was unexpected and challenging for the chatbot to recognize; and 10 types of coping strategies. Moreover, we identified specific relationships between NP types and strategies, as well as signs that users were about to abandon the chatbot, including 1) three consecutive incidences of NP, 2) consecutive use of message reformulation or switching subjects, and 3) using message reformulation as the final strategy. Based on these findings, we provide design recommendations for task-oriented chatbots, aimed at reducing NP, guiding users through such NP, and improving user experiences to reduce the cessation of chatbot use.

Developing a Personality Model for Speech-based Conversational Agents Using the Psycholexical Approach

We present the first systematic analysis of personality dimensions developed specifically to describe the personality of speech-based conversational agents. Following the psycholexical approach from psychology, we first report on a new multi-method approach to collect potentially descriptive adjectives from 1) a free description task in an online survey (228 unique descriptors), 2) an interaction task in the lab (176 unique descriptors), and 3) a text analysis of 30,000 online reviews of conversational agents (Alexa, Google Assistant, Cortana) (383 unique descriptors). We aggregate the results into a set of 349 adjectives, which are then rated by 744 people in an online survey. A factor analysis reveals that the commonly used Big Five model for human personality does not adequately describe agent personality. As an initial step to developing a personality model, we propose alternative dimensions and discuss implications for the design of agent personalities, personality-aware personalisation, and future research.

Introducing the Gamer Information-Control Framework: Enabling Access to Digital Games for People with Visual Impairment

In this paper, we present a foundation for understanding the elements that enable people with visual impairment to engage with digital games. This is defined by the gamer's relation- ships with information and with elements of control provided by the game, and is mediated through in-game metaphors and affordances when gamers interact as users or creators. This work complements previous research exploring the points of view of gamers with visual impairment by focusing on the games they play and prioritising the relationships between the key enablers of access to digital games. Using the framework to examine existing and missing components will enable de- signers to consider broader aspects of accessibility in game design.

MirrorPad: Mirror on Touchpad for Direct Pen Interaction in the Laptop Environment

There are needs for pen interaction on a laptop, and the market sees many pen-enabled laptop products. Many of these laptops can be transformed into tablets, when pen interaction is needed. In a real situation, however, a workflow often requires both keyboard and pen interactions, and such a convertible feature may not be effective. In this study, we introduce MirrorPad, a novel interface device contained in a laptop for direct pen interaction. It is both a normal touchpad and a viewport for pen interaction with a mirrored region on the screen. We report findings and decisions obtained from the design iterations that we conducted with users to refine MirrorPad toward the final design. In the user study, MirrorPad showed the same performance as that of the laptop configuration during keyboard interaction and a performance similar to that of the tablet configuration during pen interaction. The user study results confirmed that MirrorPad effectively supports a workflow, which requires interspersed keyboard and pen interactions, thereby achieving its initial goal.

Effects of Credibility Indicators on Social Media News Sharing Intent

In recent years, social media services have been leveraged to spread fake news stories. Helping people spot fake stories by marking them with credibility indicators could dissuade them from sharing such stories, thus reducing their amplification. We carried out an online study (N = 1,512) to explore the impact of four types of credibility indicators on people's intent to share news headlines with their friends on social media. We confirmed that credibility indicators can indeed decrease the propensity to share fake news. However, the impact of the indicators varied, with fact checking services being the most effective. We further found notable differences in responses to the indicators based on demographic and personal characteristics and social media usage frequency. Our findings have important implications for curbing the spread of misinformation via social media platforms.

Too Much Information: Questioning Security in a Post-Digital Society

Whilst user- and people-centered design are accepted routes for digital services, they are less commonly used in the design of technologies that control access to data and the security of information. The ubiquity of both technology and programmes such as "digital by default" as well as the weaving of digital systems into the everyday fabric of society, create an environment in which people and technology become enmeshed. Such an environment might be termed "post-digital" and its security is dependent on a people-centered approach to its design. In this paper we present a study that uses critical design techniques coupled with critical security analysis to examine how security might be approached in a post-digital context. We call for a paradigm shift towards a people-centered security practice and using a case study then make practical recommendations as to how this shift might be achieved.

PIP Kit: An Exploratory Investigation into using Lifelogging to support Disability Benefit Claimants

Disability assessment processes are complex and stressful, with claimants finding it challenging to prepare an effective account of their disabilities to support their claim. This project focuses on a disability benefit called Personal Independence Payment (PIP), which is received by millions of people with disabilities in the UK. We present a multi-stage exploratory investigation into how lifelogging could help address the challenges claimants have in accessing disability benefits. In the first study, benefit advisors participated in interviews and workshops to inform the design of PIP Kit, a highly customisable prototype elicitation diary to help disability claimants articulate their experiences. In the second study, PIP Kit was trialled by benefit claimants whilst making their actual PIP claims. We found that PIP Kit helped empower claimants in understanding the claim process and assisted in building arguments for their claims. We also have identified clear principles for supporting disability benefit claimants with technological interventions.

Officers Never Type: Examining the Persistence of Paper in e-Governance

The Global South has seen a proliferation of e-governance initiatives aimed at digitizing governmental service delivery. However, paper continues to remain the primary medium of bureaucracy. During ethnographic fieldwork at the CM Helpline, a state-wide e-governance initiative in central India, we observed that even tech-savvy bureaucrats who fully supported both the initiative and its paper-to-electronic transition ensured that paper continues to persist in abundance. Drawing upon scholarship from HCI, anthropology, and science & technology studies, we theorize this contradiction to uncover the circulations of power between people, paper, and electronic systems. We suggest that designers should recognize that new systems often disempower existing actors. The process of transition should integrate new systems into the existing ecosystem and plan for the graceful retirement of older technologies. In addition to machine errors, systems should be resilient to human errors. Finally, new systems should attend to sociocultural and historical specificities.

Swap: A Replacement-based Text Revision Technique for Mobile Devices

Text revision is an important task to ensure the accuracy of text content. Revising text on mobile devices is cumbersome and time-consuming due to the imprecise caret control and the repetitive use of the backspace. We present Swap, a novel replacement-based technique to facilitate text revision on mobile devices. We conducted two user studies to validate the feasibility and the effectiveness of Swap compared to traditional text revision techniques. Results showed that Swap reduced efforts in caret control and repetitive backspace pressing during the text revision process. Most participants preferred to use the replacement-based technique rather than backspace and caret. They also commented that the new technique is easy to learn, and it makes text revision rapid and intuitive.

ArguLens: Anatomy of Community Opinions On Usability Issues Using Argumentation Models

In open-source software (OSS), the design of usability is often influenced by the discussions among community members on platforms such as issue tracking systems (ITSs). However, digesting the rich information embedded in issue discussions can be a major challenge due to the vast number and diversity of the comments. We propose and evaluate ArguLens, a conceptual framework and automated technique leveraging an argumentation model to support effective understanding and consolidation of community opinions in ITSs. Through content analysis, we anatomized highly discussed usability issues from a large, active OSS project, into their argumentation components and standpoints. We then experimented with supervised machine learning techniques for automated argument extraction. Finally, through a study with experienced ITS users, we show that the information provided by ArguLens supported the digestion of usability-related opinions and facilitated the review of lengthy issues. ArguLens provides the direction of designing valuable tools for high-level reasoning and effective discussion about usability.

Interpreting Interpretability: Understanding Data Scientists' Use of Interpretability Tools for Machine Learning

Machine learning (ML) models are now routinely deployed in domains ranging from criminal justice to healthcare. With this newfound ubiquity, ML has moved beyond academia and grown into an engineering discipline. To that end, interpretability tools have been designed to help data scientists and machine learning practitioners better understand how ML models work. However, there has been little evaluation of the extent to which these tools achieve this goal. We study data scientists' use of two existing interpretability tools, the InterpretML implementation of GAMs and the SHAP Python package. We conduct a contextual inquiry (N=11) and a survey (N=197) of data scientists to observe how they use interpretability tools to uncover common issues that arise when building and evaluating ML models. Our results indicate that data scientists over-trust and misuse interpretability tools. Furthermore, few of our participants were able to accurately describe the visualizations output by these tools. We highlight qualitative themes for data scientists' mental models of interpretability tools. We conclude with implications for researchers and tool designers, and contextualize our findings in the social science literature.

Rapid Iron-On User Interfaces: Hands-on Fabrication of Interactive Textile Prototypes

Rapid prototyping of interactive textiles is still challenging, since manual skills, several processing steps, and expert knowledge are involved. We present Rapid Iron-On User Interfaces, a novel fabrication approach for empowering designers and makers to enhance fabrics with interactive functionalities. It builds on heat-activated adhesive materials consisting of smart textiles and printed electronics, which can be flexibly ironed onto the fabric to create custom interface functionality. To support rapid fabrication in a sketching-like fashion, we developed a handheld dispenser tool for directly applying continuous functional tapes of desired length as well as discrete patches. We introduce versatile compositions techniques that allow for creating complex circuits, utilizing commodity textile accessories and sketching custom-shaped I/O modules. We further contribute a comprehensive library of components for input, output, wiring and computing. Three example applications, results from technical experiments and expert reviews demonstrate the functionality, versatility and potential of this approach.

A Palette of Deepened Emotions: Exploring Emotional Challenge in Virtual Reality Games

Recent work introduced the notion of 'emotional challenge' promising for understanding more unique and diverse player experiences (PX). Although emotional challenge has immediately attracted HCI researchers' attention, the concept has not been experimentally explored, especially in virtual reality (VR), one of the latest gaming environments. We conducted two experiments to investigate how emotional challenge affects PX when separately from or jointly with conventional challenge in VR and PC conditions. We found that relatively exclusive emotional challenge induced a wider range of different emotions in both conditions, while the adding of emotional challenge broadened emotional responses only in VR. In both experiments, VR significantly enhanced the measured PX of emotional responses, appreciation, immersion and presence. Our findings indicate that VR may be an ideal medium to present emotional challenge and also extend the understanding of emotional (and conventional) challenge in video games.

Truncating the Y-Axis: Threat or Menace?

Bar charts with y-axes that don't begin at zero can visually exaggerate effect sizes. However, advice for whether or not to truncate the y-axis can be equivocal for other visualization types. In this paper we present examples of visualizations where this y-axis truncation can be beneficial as well as harmful, depending on the communicative and analytic intent. We also present the results of a series of crowd-sourced experiments in which we examine how y-axis truncation impacts subjective effect size across visualization types, and we explore alternative designs that more directly alert viewers to this truncation. We find that the subjective impact of axis truncation is persistent across visualizations designs, even for designs with explicit visual cues that indicate truncation has taken place. We suggest that designers consider the scale of the meaningful effect sizes and variation they intend to communicate, regardless of the visual encoding.

Bot or not? User Perceptions of Player Substitution with Deep Player Behavior Models

Many online games suffer when players drop off due to lost connections or quitting prematurely, which leads to match terminations or game-play imbalances. While rule-based outcome evaluations or substitutions with bots are frequently used to mitigate such disruptions, these techniques are often perceived as unsatisfactory. Deep learning methods have successfully been used in deep player behavior modelling (DPBM) to produce non-player characters or bots which show more complex behavior patterns than those modelled using traditional AI techniques. Motivated by these findings, we present an investigation of the player-perceived awareness, believability and representativeness, when substituting disconnected players with DPBM agents in an online-multiplayer action game. Both quantitative and qualitative outcomes indicate that DPBM agent substitutes perform similarly to human players and that players were unable to detect substitutions. Notably, players were in fact able to detect substitution with agents driven by more traditional heuristics.

Decoding Intent With Control Theory: Comparing Muscle Versus Manual Interface Performance

Manual device interaction requires precise coordination which may be difficult for users with motor impairments. Muscle interfaces provide alternative interaction methods that may enhance performance, but have not yet been evaluated for simple (eg. mouse tracking) and complex (eg. driving) continuous tasks. Control theory enables us to probe continuous task performance by separating user input into intent and error correction to quantify how motor impairments impact device interaction. We compared the effectiveness of a manual versus a muscle interface for eleven users without and three users with motor impairments performing continuous tasks. Both user groups preferred and performed better with the muscle versus the manual interface for the complex continuous task. These results suggest muscle interfaces and algorithms that can detect and augment user intent may be especially useful for future design of interfaces for continuous tasks.

"All in the Same Boat": Tradeoffs of Voice Assistant Ownership for Mixed-Visual-Ability Families

A growing body of evidence suggests Voice Assistants (VAs) are highly valued by people with vision impairments (PWVI) and much less so by sighted users. Yet, many are deployed in homes where both PWVI and sighted family members reside. Researchers have yet to study whether VA use and perceived benefits are affected in settings where one person has a visual impairment and others do not. We conducted six in-depth interviews with partners to understand patterns of domestic VA use in mixed-visual-ability families. Although PWVI were more motivated to acquire VAs, used them more frequently, and learned more proactively about their features, partners with vision identified similar benefits and disadvantages of having VAs in their home. We found that the universal usability of VAs both equalizes experience across abilities and presents complex tradeoffs for families-regarding interpersonal relationships, domestic labor, and physical safety-which are weighed against accessibility benefits for PWVI and complicate the decision to fully integrate VAs in the home.

An Interaction Design for Machine Teaching to Develop AI Tutors

Intelligent tutoring systems (ITSs) have consistently been shown to improve the educational outcomes of students when used alone or combined with traditional instruction. However, building an ITS is a time-consuming process which requires specialized knowledge of existing tools. Extant authoring methods, including the Cognitive Tutor Authoring Tools' (CTAT) example-tracing method and SimStudent's Authoring by Tutoring, use programming-by-demonstration to allow authors to build ITSs more quickly than they could by hand programming with model-tracing. Yet these methods still suffer from long authoring times or difficulty creating complete models. In this study, we demonstrate that Simulated Learners built with the Apprentice Learner (AL) Framework can be combined with a novel interaction design that emphasizes model transparency, input flexibility, and problem solving control to enable authors to achieve greater model completeness in less time than existing authoring methods.

Unfabricate: Designing Smart Textiles for Disassembly

Smart textiles development is combining computing and textile technologies to create tactile, functional objects such as smart garments, soft medical devices, and space suits. However, the field also combines the massive waste streams of both the digital electronics and textiles industries. The following work explores how HCI researchers might be poised to address sustainability and waste in future smart textiles development through interventions at design time. Specifically, we perform a design inquiry into techniques and practices for reclaiming and reusing smart textiles materials and explore how such techniques can be integrated into smart textiles design tools. Beginning with a practice in sustainable or "slow" fashion, unravelling a garment into yarn, the suite of explorations titled "Unfabricate" probes values of time and labor in crafting a garment; speculates how a smart textile garment may be designed with reuse in mind; and imagines how electronic and textile components may be given new life in novel uses.

Bridging the Virtual and Real Worlds: A Preliminary Study of Messaging Notifications in Virtual Reality

Virtual reality (VR) platforms provide their users with immersive virtual environments, but disconnect them from real-world events. The increasing length of VR sessions can therefore be expected to boost users' needs to obtain information about external occurrences such as message arrival. Yet, how and when to present these real-world notifications to users engaged in VR activities remains underexplored. We conducted an experiment to investigate individuals' receptivity during four VR activities (Loading, 360 Video, Treasure Hunt, Rhythm Game) to message notifications delivered using three types of displays (head-mounted, controller, and movable panel). While higher engagement generally led to higher perceptions that notifications were ill-timed and/or disruptive, the suitability of notification displays to VR activities was influenced by the time-sensitiveness of VR content, overlapping use of modalities for delivering alerts, the display locations, and a requirement that the display be moved for notifications to be seen. Specific design suggestions are also provided.

A Human-Centered Review of Algorithms used within the U.S. Child Welfare System

The U.S. Child Welfare System (CWS) is charged with improving outcomes for foster youth; yet, they are overburdened and underfunded. To overcome this limitation, several states have turned towards algorithmic decision-making systems to reduce costs and determine better processes for improving CWS outcomes. Using a human-centered algorithmic design approach, we synthesize 50 peer-reviewed publications on computational systems used in CWS to assess how they were being developed, common characteristics of predictors used, as well as the target outcomes. We found that most of the literature has focused on risk assessment models but does not consider theoretical approaches (e.g., child-foster parent matching) nor the perspectives of caseworkers (e.g., case notes). Therefore, future algorithms should strive to be context-aware and theoretically robust by incorporating salient factors identified by past research. We provide the HCI community with research avenues for developing human-centered algorithms that redirect attention towards more equitable outcomes for CWS.

MicroMentor: Peer-to-Peer Software Help Sessions in Three Minutes or Less

While synchronous one-on-one help for software learning is rich and valuable, it can be difficult to find and connect with someone who can provide assistance. Through a formative user study, we explore the idea of fixed-duration, one-on-one help sessions and find that 3 minutes is often enough time for novice users to explain their problem and receive meaningful help from an expert. To facilitate this type of interaction, we developed MicroMentor, an on-demand help system that connects users via video chat for 3-minute help sessions. MicroMentor automatically attaches relevant supplementary materials and uses contextual information, such as command history and expertise, to encourage the most qualified users to accept incoming requests. These help sessions are recorded and archived, building a bank of knowledge that can further help a broader audience. Through a user study, we find MicroMentor to be useful and successful in connecting users for short teaching moments.

In Search of Forms for Evocative and Generative Reflection: Exploratory Studies and a Design Proposal

Today an increasing number of personal informatics tools and platforms support intended behavior change and goal achievement through data-based self-reflection. The scope of self-reflection expands with emerging sources, goals, and challenges of human well-being, demanding for reframing recent computer-mediated reflective practice. This study investigates a broader range of contexts and forms of self-reflection that support navigating one's mind and goals beyond achieving preset goals. This paper describes contemporary issues on human well-being and two exploratory studies-one conducted in a traveling artists' residency and the other in a design studio class-which surveyed various triggers, contexts, and forms of self-reflection. By connecting the insights from the two studies, I propose evocative and generative reflection as an alternative perspective to tracking-based, goal-oriented reflection and discuss implications for the design for reflection with a focus on the creative dimension of human well-being.

Will the Crowd Game the Algorithm?: Using Layperson Judgments to Combat Misinformation on Social Media by Downranking Distrusted Sources

How can social media platforms fight the spread of misinformation? One possibility is to use newsfeed algorithms to downrank content from sources that users rate as untrustworthy. But will laypeople be handicapped by motivated reasoning or lack of expertise, and thus unable to identify misinformation sites? And will they "game" this crowdsourcing mechanism in order to promote content that aligns with their partisan agendas? We conducted a survey experiment in which =984 Americans indicated their trust in numerous news sites. To study the tendency of people to game the system, half of the participants were told their responses would inform social media ranking algorithms. Participants trusted mainstream sources much more than hyper-partisan or fake news sources, and their ratings were highly correlated with professional fact-checker judgments. Critically, informing participants that their responses would influence ranking algorithms did not diminish these results, despite the manipulation increasing the political polarization of trust ratings.

BISHARE: Exploring Bidirectional Interactions Between Smartphones and Head-Mounted Augmented Reality

In pursuit of a future where HMD devices can be used in tandem with smartphones and other smart devices, we present BISHARE, a design space of cross-device interactions between smartphones and ARHMDs. Our design space is unique in that it is bidirectional in nature, as it examines how both the HMD can be used to enhance smartphone tasks, and how the smartphone can be used to enhance HMD tasks. We then present an interactive prototype that enables cross-device interactions across the proposed design space. A 12-participant user study demonstrates the promise of the design space and provides insights, observations, and guidance for the future.

MagTouch: Robust Finger Identification for a Smartwatch Using a Magnet Ring and a Built-in Magnetometer

Completing tasks on smartwatches often requires multiple gestures due to the small size of the touchscreens and the lack of sufficient number of touch controls that are easily accessible with a finger. We propose to increase the number of functions that can be triggered with the touch gesture by enabling a smartwatch to identify which finger is being used. We developed MagTouch, a method that uses a magnetometer embedded in an off-the-shelf smartwatch. It measures the magnetic field of a magnet fixed to a ring worn on the middle finger. By combining the measured magnetic field and the touch location on the screen, MagTouch recognizes which finger is being used. The tests demonstrated that MagTouch can differentiate among the three fingers used to make contacts at a success rate of 95.03%.

Teddy: A System for Interactive Review Analysis

Reviews are integral to e-commerce services and products. They contain a wealth of information about the opinions and experiences of users, which can help better understand consumer decisions and improve user experience with products and services. Today, data scientists analyze reviews by developing rules and models to extract, aggregate, and understand information embedded in the review text. However, working with thousands of reviews, which are typically noisy incomplete text, can be daunting without proper tools. Here we first contribute results from an interview study that we conducted with fifteen data scientists who work with review text, providing insights into their practices and challenges. Results suggest data scientists need interactive systems for many review analysis tasks. Towards a solution, we then introduce Teddy, an interactive system that enables data scientists to quickly obtain insights from reviews and improve their extraction and modeling pipelines.

E-Textile Microinteractions: Augmenting Twist with Flick, Slide and Grasp Gestures for Soft Electronics

E-textile microinteractions advance cord-based interfaces by enabling the simultaneous use of precise continuous control and casual discrete gestures. We leverage the recently introduced I/O Braid sensing architecture to enable a series of user studies and experiments which help design suitable interactions and a real-time gesture recognition pipeline. Informed by a gesture elicitation study with 36 participants, we developed a user-dependent classifier for eight discrete gestures with 94% accuracy for 12 participants. In a formal evaluation we show that we can enable precise manipulation with the same architecture. Our quantitative targeting experiment suggests that twisting is faster than existing headphone button controls and is comparable in speed to a capacitive touch surface. Qualitative interview feedback indicates a preference for I/O Braid's interaction over that of in-line headphone controls. Our applications demonstrate how continuous and discrete gestures can be combined to form new, integrated e-textile microinteraction techniques for real-time continuous control, discrete actions and mode switching.

Evaluating the Effect of Timeline Shape on Visualization Task Performance

Timelines are commonly represented on a horizontal line, which is not necessarily the most effective way to visualize temporal event sequences. However, few experiments have evaluated how timeline shape influences task performance. We present the design and results of a controlled experiment run on Amazon Mechanical Turk (n=192) in which we evaluate how timeline shape affects task completion time, correctness, and user preference. We tested 12 combinations of 4 shapes --- horizontal line, vertical line, circle, and spiral — and 3 data types — recurrent, non-recurrent, and mixed event sequences. We found good evidence that timeline shape meaningfully affects user task completion time but not correctness and that users have a strong shape preference. Building on our results, we present design guidelines for creating effective timeline visualizations based on user task and data types. A free copy of this paper, the evaluation stimuli and data, and code are available

OralCam: Enabling Self-Examination and Awareness of Oral Health Using a Smartphone Camera

Due to a lack of medical resources or oral health awareness, oral diseases are often left unexamined and untreated, affecting a large population worldwide. With the advent of low-cost, sensor-equipped smartphones, mobile apps offer a promising possibility for promoting oral health. However, to the best of our knowledge, no mobile health (mHealth) solutions can directly support a user to self-examine their oral health condition. This paper presents OralCam, the first interactive app that enables end-users' self-examination of five common oral conditions (diseases or early disease signals) by taking smartphone photos of one's oral cavity. OralCam allows a user to annotate additional information (e.g. living habits, pain, and bleeding) to augment the input image, and presents the output hierarchically, probabilistically and with visual explanations to help a laymen user understand examination results. Developed on our in-house dataset that consists of 3,182 oral photos annotated by dental experts, our deep learning based framework achieved an average detection sensitivity of 0.787 over five conditions with high localization accuracy. In a week-long in-the-wild user study (N=18), most participants had no trouble using OralCam and interpreting the examination results. Two expert interviews further validate the feasibility of OralCam for promoting users' awareness of oral health.

Investigating the Opportunities for Technologies to Enhance QoL with Stroke Survivors and their Families

There are over 80 million stroke survivors globally, making it the main cause of long-term disability worldwide. Not only do the challenges associated with stroke affect the quality of life (QoL) of survivors, but also of their families. To explore these challenges and define design opportunities for technologies to improve the QoL of both stakeholders, we conducted semi-structured interviews with 10 survivors and one of their family members. We uncovered three major interlinked themes: strategies to cope with technological barriers, the (in)adequacy of assistive technologies, and limitations of the rehabilitation process. Findings highlight multiple design opportunities, including the need for meaningful patient-centered tools and methods to improve rehabilitation effectiveness, emotion-aware computing for family emotional support, and re-thinking the nature of assistive technologies to consider the perception of transitory stroke-related disabilities. We thus argue for a new class of dual-purpose technologies that fit survivors' abilities while promoting the regain of function.

User Experiences with Online Status Indicators

Online status indicators (OSIs) improve online communication by helping users convey and assess availability, but they also let users infer potentially sensitive information about one another. We surveyed 200 smartphone users to understand the extent to which users are aware of information shared via OSIs and the extent to which this shapes their behavior. Despite familiarity with OSIs, participants misunderstand many aspects of OSIs, and they describe carefully curating and seeking to control their self-presentation via OSIs. Some users further report leveraging OSI-conveyed information for problematic and malicious purposes. Drawing on existing constructs of app dependence (i.e., when users contort their behavior to meet an app's demands) and app enablement (i.e., when apps enable users to engage in behaviors they feel good about), we demonstrate that current OSI design patterns promote app dependence, and we call for a shift toward OSI designs that are more enabling for users.

Opportunities for Enhancing Access and Efficacy of Peer Sponsorship in Substance Use Disorder Recovery

Substance use disorders (SUDs) are characterized by an inability to decrease a substance use (e.g., alcohol or opioids) despite negative repercussions. SUDs are clinically diagnosable, hazardous, and considered a public health issue. Sponsorship, a specialized type of peer mentorship, is vital in the recovery process and originates from 12-step fellowship programs such as Alcoholics Anonymous (AA) and Narcotics Anonymous (NA). To investigate sponsorship relationship practices and to identify design opportunities for digitally-mediated peer support, we conducted 27 in-depth interviews with members of AA and NA. We identified five key sponsorship relationship practices relevant for designing social computing tools to support sponsorship and recovery: 1) assessing dyadic compatibility, 2) managing sponsorship with or without technology, 3) establishing boundaries, 4) building a peer support network, and 5) managing anonymity. We identify social computing and digitally-mediated design opportunities and implications.

Next Steps for Human-Computer Integration

Human-Computer Integration (HInt) is an emerging paradigm in which computational and human systems are closely interwoven. Integrating computers with the human body is not new. however, we believe that with rapid technological advancements, increasing real-world deployments, and growing ethical and societal implications, it is critical to identify an agenda for future research. We present a set of challenges for HInt research, formulated over the course of a five-day workshop consisting of 29 experts who have designed, deployed and studied HInt systems. This agenda aims to guide researchers in a structured way towards a more coordinated and conscientious future of human-computer integration.

JumpVR: Jump-Based Locomotion Augmentation for Virtual Reality

One of the great benefits of virtual reality (VR) is the implementation of features that go beyond realism. Common "unrealistic" locomotion techniques (like teleportation) can avoid spatial limitation of tracking, but minimize potential benefits of more realistic techniques (e.g. walking). As an alternative that combines realistic physical movement with hyper-realistic virtual outcome, we present JumpVR, a jump-based locomotion augmentation technique that virtually scales users' physical jumps. In a user study (N=28), we show that jumping in VR (regardless of scaling) can significantly increase presence, motivation and immersion compared to teleportation, while largely not increasing simulator sickness. Further, participants reported higher immersion and motivation for most scaled jumping variants than forward-jumping. Our work shows the feasibility and benefits of jumping in VR and explores suitable parameters for its hyper-realistic scaling. We discuss design implications for VR experiences and research.

AutoGain: Gain Function Adaptation with Submovement Efficiency Optimization

A well-designed control-to-display gain function can improve pointing performance with indirect pointing devices like trackpads. However, the design of gain functions is challenging and mostly based on trial and error. AutoGain is a novel method to individualize a gain function for indirect pointing devices in contexts where cursor trajectories can be tracked. It gradually improves pointing efficiency by using a novel submovement-level tracking+optimization technique that minimizes aiming error (undershooting/overshooting) for each submovement. We first show that AutoGain can produce, from scratch, gain functions with performance comparable to commercial designs, in less than a half-hour of active use. Second, we demonstrate AutoGain's applicability to emerging input devices (here, a Leap Motion controller) with no reference gain functions. Third, a one-month longitudinal study of normal computer use with AutoGain showed performance improvements from participants' default functions.

When the Civic Turn turns Digital: Designing Safe and Secure Refugee Resettlement

Across Europe, refugees are required to engage with the "civic turn" -- a process of integrating refugees into the social and cultural aspects of the new land. Over a two-year period, we engaged 89 refugees settling in Sweden, to explore how accelerated and digitalised resettlement processes shape the civic turn. Framed within wider literature on transitioning and everyday insecurities, we show how this "digital turn" exacerbates existing barriers to resettlement experienced by refugees. By critically analysing these barriers, we reveal how the civic turn rests upon a series of everyday social and cultural practices and relations, which are largely ignored in digital service design. We show how this leads to a "vacuum" for our participants. We call on the HCI community to engage with this vacuum and understand resettlement as encompassing multiple digitally-mediated transitional phases of citizenry. We do so by focusing on the digitalisation processes shaping these transitions.

Sociality and Skill Sharing in the Garden

Gardening is an activity that involves a number of dimensions of increasing interest to HCI and CSCW researchers, including recreation, sustainability, and engagement with nature. This paper considers the garden setting in order to understand the role that collaborative and social computing technologies might play for practitioners engaging in outdoor skilled activities. We conducted participant observations with nine experienced gardeners aged 22-71 years. Through this process, we find that gardeners continuously configure their environments to accommodate their preferences for sociality. They share embodied skills and help others attune to sensory information in person, but also influence learning through the features in their garden that are observed by others. This paper provides an understanding of sociality in the garden, highlights skill sharing as a key domain for design in this space, and contributes design considerations for collaborative technologies in outdoor settings.

Keep Calm and Ride Along: Passenger Comfort and Anxiety as Physiological Responses to Autonomous Driving Styles

Autonomous vehicles have been rapidly progressing towards full autonomy using fixed driving styles, which may differ from individual passenger preferences. Violating these preferences may lead to passenger discomfort or anxiety. We studied passenger responses to different driving style parameters in a physical autonomous vehicle. We collected galvanic skin response, heart rate, and eye-movement patterns from 20 participants, along with self-reported comfort and anxiety scores. Our results show that the presence and proximity of a lead vehicle not only raised the level of all measured physiological responses, but also exaggerated the existing effect of the longitudinal acceleration and jerk parameters. Skin response was also found to be a significant predictor of passenger comfort and anxiety. By using multiple independent events to isolate different driving style parameters, we demonstrate a method to control and analyze such parameters in future studies.

Autocomplete Element Fields

Aggregate elements are ubiquitous in natural and man-made objects. Interactively authoring these elements with varying anisotropy and deformability can require high artistic skills and manual labor. To reduce input workload and enhance output quality, we present an autocomplete system that can help users distribute and align such elements over different domains. Through a brushing interface, users can place and mix a few elements, and let our system automatically populate more elements for the remaining output. Furthermore, aggregate elements often require proper direction/scalar fields for proper arrangements, but fully specifying such fields across entire domains can be difficult or inconvenient for ordinary users. To address this usability challenge, we formulate element fields that can smoothly orient all the elements based on partial user specifications without requiring full input fields in any step. We validate our prototype system with a pilot user study and show applications in design, collage, and modeling.

Sprayable User Interfaces: Prototyping Large-Scale Interactive Surfaces with Sensors and Displays

We present Sprayable User Interfaces: room-sized interactive surfaces that contain sensor and display elements created by airbrushing functional inks. Since airbrushing is inherently mobile, designers can create large-scale user interfaces on complex 3D geometries where existing stationary fabrication methods fail. To enable Sprayable User Interfaces, we developed a novel design and fabrication pipeline that takes a desired user interface layout as input and automatically generates stencils for airbrushing the layout onto a physical surface. After fabricating stencils from cardboard or projecting stencils digitally, designers spray each layer with an airbrush, attach a microcontroller to the user interface, and the interface is ready to be used. Our technical evaluation shows that Sprayable User Interfaces work on various geometries and surface materials, such as porous stone and rough wood. We demonstrate our system with several application examples including interactive smart home applications on a wall and a soft leather sofa, an interactive smart city application, and interactive architecture in public office spaces.

Understanding Users' Perception Towards Automated Personality Detection with Group-specific Behavioral Data

Thanks to advanced sensing and logging technology, automatic personality assessment (APA) with users' behavioral data in the workplace is on the rise. While previous work has focused on building APA systems with high accuracy, little research has attempted to understand users' perception towards APA systems. To fill this gap, we take a mixed-methods approach: we (1) designed a survey (n=89) to understand users'social workplace behavior both online and offline and their privacy concerns; (2) built a research probe that detects personality from online and offline data streams with up to 81.3% accuracy, and deployed it for three weeks in Korea (n=32); and (3) conducted post-interviews (n=9). We identify privacy issues in sharing data and system-induced change in natural behavior as important design factors for APA systems. Our findings suggest that designers should consider the complex relationship between users' perception and system accuracy for a more user-centered APA design.

Re-Shape: A Method to Teach Data Ethics for Data Science Education

Data has become central to the technologies and services that human-computer interaction (HCI) designers make, and the ethical use of data in and through these technologies should be given critical attention throughout the design process. However, there is little research on ethics education in computer science that explicitly addresses data ethics. We present and analyze Re-Shape, a method to teach students about the ethical implications of data collection and use. Re-Shape, as part of an educational environment, builds upon the idea of cultivating care and allows students to collect, process, and visualize their physical movement data in ways that support critical reflection and coordinated classroom activities about data, data privacy, and human-centered systems for data science. We also use a case study of Re-Shape in an undergraduate computer science course to explore prospects and limitations of instructional designs and educational technology such as Re-Shape that leverage personal data to teach data ethics.

ARMath: Augmenting Everyday Life with Math Learning

We introduce ARMath, a mobile Augmented Reality (AR) system that allows ch ildren to discover mathematical concepts in familiar, ord inary objects and engage with math problems in meaningful contexts. Leveraging advanced computer vision, ARMath recognizes everyday objects, visualizes their mathematical attributes, and turns them into tangible or virtual manipulatives. Using the manipulatives, children can solve problems that situate math operations or concepts in specific everyday contexts. Informed by four participatory design sessions with teachers and children, we developed five ARMath modules to support basic arithmetic and 2D geometry. We also conducted an exploratory evaluation of ARMath with 27 children (ages 5-8) at a local children's museum. Our findings demonstrate how ARMath engages children in math learning, how failures in AI can be used as learning opportunities, and challenges that children face when using ARMath.

How Domain Experts Create Conceptual Diagrams and Implications for Tool Design

Conceptual diagrams are used extensively to understand abstract relationships, explain complex ideas, and solve difficult problems. To illustrate concepts effectively, experts find appropriate visual representations and translate concepts into concrete shapes. This translation step is not supported explicitly by current diagramming tools. This paper investigates how domain experts create conceptual diagrams via semi-structured interviews with 18 participants from diverse backgrounds. Our participants create, adapt, and reuse visual representations using both sketches and digital tools. However, they had trouble using current diagramming tools to transition from sketches and reuse components from earlier diagrams. Our participants also expressed frustration with the slow feedback cycles and barriers to automation of their tools. Based on these results, we suggest four opportunities of diagramming tools — exploration support, representation salience, live engagement, and vocabulary correspondence — that together enable a natural diagramming experience. Finally, we discuss possibilities to leverage recent research advances to develop natural diagramming tools.

The Experience of Guided Online Therapy: A Longitudinal, Qualitative Analysis of Client Feedback in a Naturalistic RCT

Internet-delivered Cognitive Behavioural Therapy (iCBT) is an effective treatment for depression and anxiety disorders. However longitudinal qualitative research into the client's subjective experience of this form of treatment ?in the wild' is relatively scarce. We present an analysis of secondary outcomes in a naturalistic RCT conducted within the UK's Improving Access to Psychological Therapies programme. We evaluated clients' expectations, experience, and context of usage of iCBT, across three timepoints. Results are discussed in terms of the creation of a therapeutic space online, the impact of hope, expectations and personal factors on the therapeutic experience, iCBT as "therapy on the go" and developing skills for life. While iCBT on the whole provides a positive, supportive and therapeutic experience for clients, the study identified managing expectations, polarized preferences, momentary help-seeking and long-term support as important aspects of the experience to consider in future design.

Smart Home Beyond the Home: A Case for Community-Based Access Control

As smart devices are becoming commonplace in homes, we need to explore the needs of not just the residents of the home, but also of secondary stakeholders who may be granted access to these devices from outside of the home. We conducted a mixed methods study, which included a survey of 163 smart home device owners and a follow-up interview with 13 individuals who currently share their smart home devices with others outside of their home. Nearly half (47.8%) of our survey participants shared at least one smart home device with someone that did not live with them. Individuals sought greater safety and security by providing remote access to trusted family members or friends. By understanding users' perspectives about privacy and trust in relation to sharing smart home devices beyond the home, we build a case for community-based access control of smart home devices in the Internet of Things.

Race Yourselves: A Longitudinal Exploration of Self-Competition Between Past, Present, and Future Performances in a VR Exergame

Participating in competitive races can be a thrilling experience for athletes, involving a rush of excitement and sensations of flow, achievement, and self-fulfilment. However, for non-athletes, the prospect of competition is often a scary one which affects intrinsic motivation negatively, especially for less fit, less competitive individuals. We propose a novel method making the positive racing experience accessible to non-athletes using a high-intensity cycling VR exergame: by recording and replaying all their previous gameplay sessions simultaneously, including a projected future performance, players can race against a crowd of "ghost" avatars representing their individual fitness journey. The experience stays relevant and exciting as every race adds a new competitor. A longitudinal study over four weeks and a cross-sectional study found that the new method improves physical performance, intrinsic motivation, and flow compared to a non-competitive exergame. Additionally, the longitudinal study provides insights into the longer-term effects of VR exergames.

Do I Look Like a Criminal? Examining how Race Presentation Impacts Human Judgement of Recidivism

Understanding how racial information impacts human decision making in online systems is critical in today's world. Prior work revealed that race information of criminal defendants, when presented as a text field, had no significant impact on users' judgements of recidivism. We replicated and extended this work to explore how and when race information influences users' judgements, with respect to the saliency of presentation. Our results showed that adding photos to the race labels had a significant impact on recidivism predictions for users who identified as female, but not for those who identified as male. The race of the defendant also impacted these results, with black defendants being less likely to be predicted to recidivate compared to white defendants. These results have strong implications for how system-designers choose to display race information, and cautions researchers to be aware of gender and race effects when using Amazon Mechanical Turk workers.

It Is Your Turn: Collaborative Ideation With a Co-Creative Robot through Sketch

Co-creative systems have been widely explored in the field of computational creativity. However, existing AI partners of these systems are mostly virtual agents. As sketching on paper with embodied robots could be more engaging for designers' early-stage ideation and collaborative practices, we envision the possibility of Cobbie, a mobile robot that ideates iteratively with designers by generating creative and diverse sketches. To evaluate the differences in co-creativity and user experience between the co-creative robots and virtual agents, we conducted a comparative experiment and analyzed the data collected from quantitative scales, observation, and semi-structured interview. The results reveal that Cobbie is more satisfying in motivating exploration, provoking unexpected ideas and engaging designers in the collaborative ideation process. Based on these findings, we discussed the prospects of co-creative robots for future developments of human-AI collaborative systems.

MissIt: Using Missed Calls for Free, Extremely Low Bit-Rate Communication in Developing Regions

Mobile devices have become the primary mode for Internet access in developing countries. Yet typical data plans and SMS costs can be overwhelming for low income users in these countries. In this paper, we explore the design and usability of a free but extremely low bit rate communication channel to address this challenge. We propose, a data communication channel that uses to transmit messages between phones, thereby sacrificing performance in exchange for low cost. While the data rate of is extremely low (<1 bps), our prototype implementation and small scale user studies explore the feasibility of this idea for different types of messaging scenarios. Our results show that could be a viable option for messaging scenarios that require short, pre-determined responses (e.g., survey questions) while for traditional SMS-style messaging, a suitable user interface and other customizations are likely required to make it a viable option for users.

Examining Design Choices of Questionnaires in VR User Studies

Questionnaires are among the most common research tools in virtual reality (VR) user studies. Transitioning from virtuality to reality for giving self-reports on VR experiences can lead to systematic biases. VR allows to embed questionnaires into the virtual environment which may ease participation and avoid biases. To provide a cohesive picture of methods and design choices for questionnaires in VR (inVRQ), we discuss 15 inVRQ studies from the literature and present a survey with 67 VR experts from academia and industry. Based on the outcomes, we conducted two user studies in which we tested different presentation and interaction methods of inVRQs and evaluated the usability and practicality of our design. We observed comparable completion times between inVRQs and questionnaires outside VR (nonVRQs) with higher enjoyment but lower usability for \inVRQs. These findings advocate the application of inVRQs and provide an overview of methods and considerations that lay the groundwork for inVRQ design.

Unmet Needs and Opportunities for Mobile Translation AI

Translation apps and devices are often presented in the context of providing assistance while traveling abroad. However, the spectrum of needs for cross-language communication is much wider. To investigate these needs, we conducted three studies with populations spanning socioeconomic status and geographic regions: (1) United States-based travelers, (2) migrant workers in India, and (3) immigrant populations in the United States. We compare frequent travelers' perception and actual translation needs with those of the two migrant communities. The latter two, with low language proficiency, have the greatest translation needs to navigate their daily lives. However, current mobile translation apps do not meet these needs. Our findings provide new insights on the usage practices and limitations of mobile translation tools. Finally, we propose design implications to help apps better serve these unmet needs.

Button Simulation and Design via FDVV Models

Designing a push-button with desired sensation and performance is challenging because the mechanical construction must have the right response characteristics. Physical simulation of a button's force-displacement (FD) response has been studied to facilitate prototyping; however, the simulations' scope and realism have been limited. In this paper, we extend FD modeling to include vibration (V) and velocity-dependence characteristics (V). The resulting FDVV models better capture tactility characteristics of buttons, including snap. They increase the range of simulated buttons and the perceived realism relative to FD models. The paper also demonstrates methods for obtaining these models, editing them, and simulating accordingly. This end-to-end approach enables the analysis, prototyping, and optimization of buttons, and supports exploring designs that would be hard to implement mechanically.

Exploring Visual Information Flows in Infographics

Infographics are engaging visual representations that tell an informative story using a fusion of data and graphical elements. The large variety of infographic design poses a challenge for their high-level analysis. We use the concept of Visual Information Flow (VIF), which is the underlying semantic structure that links graphical elements to convey the information and story to the user. To explore VIF, we collected a repository of over 13K infographics. We use a deep neural network to identify visual elements related to information, agnostic to their various artistic appearances. We construct the VIF by automatically chaining these visual elements together based on Gestalt principles. Using this analysis, we characterize the VIF design space by a taxonomy of 12 different design patterns. Exploring in a real-world infographic dataset, we discuss the design space and potentials of VIF in light of this taxonomy.

Informing the Design of Privacy-Empowering Tools for the Connected Home

Connected devices in the home represent a potentially grave new privacy threat due to their unfettered access to the most personal spaces in people's lives. Prior work has shown that despite concerns about such devices, people often lack sufficient awareness, understanding, or means of taking effective action. To explore the potential for new tools that support such needs directly we developed Aretha, a privacy assistant technology probe that combines a network disaggregator, personal tutor, and firewall, to empower end-users with both the knowledge and mechanisms to control disclosures from their homes. We deployed Aretha in three households over six weeks, with the aim of understanding how this combination of capabilities might enable users to gain awareness of data disclosures by their devices, form educated privacy preferences, and to block unwanted data flows. The probe, with its novel affordances-and its limitations-prompted users to co-adapt, finding new control mechanisms and suggesting new approaches to address the challenge of regaining privacy in the connected home.

Virtual Reality Games for People Using Wheelchairs

Virtual Reality (VR) holds the promise of providing engaging embodied experiences, but little is known about how people with disabilities engage with it. We explore challenges and opportunities of VR gaming for wheelchair users. First, we present findings from a survey that received 25 responses and gives insights into wheelchair users' motives to (non-) engage with VR and their experiences. Drawing from this survey, we derive design implications which we tested through implementation and qualitative evaluation of three full-body VR game prototypes with 18 participants. Our results show that VR gaming engages wheelchair users, though nuanced consideration is required for the design of embodied immersive experiences for minority bodies, and we illustrate how designers can create meaningful, positive experiences.

A View on the Viewer: Gaze-Adaptive Captions for Videos

Subtitles play a crucial role in cross-lingual distribution of multimedia content and help communicate information where auditory content is not feasible (loud environments, hearing impairments, unknown languages). Established methods utilize text at the bottom of the screen, which may distract from the video. Alternative techniques place captions closer to related content (e.g., faces) but are not applicable to arbitrary videos such as documentations. Hence, we propose to leverage live gaze as indirect input method to adapt captions to individual viewing behavior. We implemented two gaze-adaptive methods and compared them in a user study (n=54) to traditional captions and audio-only videos. The results show that viewers with less experience with captions prefer our gaze-adaptive methods as they assist them in reading. Furthermore, gaze distributions resulting from our methods are closer to natural viewing behavior compared to the traditional approach. Based on these results, we provide design implications for gaze-adaptive captions.

Emoji Accessibility for Visually Impaired People

Emoji are graphical symbols that appear in many aspects of our lives. Worldwide, around 36 million people are blind and 217 million have a moderate to severe visual impairment. This portion of the population may use and encounter emoji, yet it is unclear what accessibility challenges emoji introduce. We first conducted an online survey with 58 visually impaired participants to understand how they use and encounter emoji online, and the challenges they experience. We then conducted 11 interviews with screen reader users to understand more about the challenges reported in our survey findings. Our interview findings demonstrate that technology is both an enabler and a barrier, emoji descriptors can hinder communication, and therefore the use of emoji impacts social interaction. Using our findings from both studies, we propose best practice when using emoji and recommendations to improve the future accessibility of emoji for visually impaired people.

BodyLights: Open-Ended Augmented Feedback to Support Training Towards a Correct Exercise Execution

Technologies targeting a correct execution of physical training exercises typically use pre-determined models for what they consider correct, automatizing instruction and feedback. This falls short on catering to diverse trainees and exercises. We explore an alternative design approach, in which technology provides open-ended feedback for trainers and trainees to use during training. With a personal trainer we designed the augmentation of 18 strength training exercises with BodyLights: 3D printed wearable projecting lights that augment body movement and orientation. To study them, 15 trainees at different skill levels trained three times with our personal trainer and BodyLights. Our findings show that BodyLights catered to a wide range of trainees and exercises, and supported understanding, executing and correcting diverse technique parameters. We discuss design features and methodological aspects that allowed this; and what open-ended feedback offered in comparison to current technology approaches to support training towards a correct exercise execution.

ShArc: A Geometric Technique for Multi-Bend/Shape Sensing

We present ShArc, a precision, geometric measurement technique for building multi-bend/shape sensors. ShArc sensors are made from flexible strips that can be dynamically formed into complex curves in a plane. They measure local curvature by noting the relative shift between the inner and outer layers of the sensor at many points and model shape as a series of connected arcs. Unlike jointed systems where angular errors sum with each joint measured, ShArc sensors do not accumulate angular error as more measurement points are added. This allows for inexpensive, robust sensors that can accurately model curves with multiple bends. To demonstrate the efficacy of this technique, we developed a capacitive ShArc sensor and evaluated its performance. We conclude with examples of how ShArc sensors can be employed in applications like gesture input devices, user interface controllers, human motion tracking and angular measurement of free-form objects.

Robots for Inclusive Play: Co-designing an Educational Game With Visually Impaired and sighted Children

Despite being included in mainstream schools, visually impaired children still face barriers to social engagement and participation. Games could potentially help, but games that cater for both visually impaired and sighted players are scarce. We used a co-design approach to design and evaluate a robot-based educational game that could be inclusive of both visually impaired and sighted children in the context of mainstream education. We ran a focus group discussion with visual impairment educators to understand barriers to inclusive play. And then a series of co-design workshops to engage visually impaired and sighted children and educators in learning about robot technology and exploring its potential to support inclusive play experiences. We present design guidelines and an evaluation workshop of a game prototype, demonstrating group dynamics conducive to collaborative learning experiences, including shared goal setting/execution, closely coupled division of labour, and interaction symmetry.

Cheat Sheets for Data Visualization Techniques

This paper introduces the concept of 'cheat sheets' for data visualization techniques, a set of concise graphical explanations and textual annotations inspired by infographics, data comics, and cheat sheets in other domains. Cheat sheets aim to address the increasing need for accessible material that supports a wide audience in understanding data visualization techniques, their use, their fallacies and so forth. We have carried out an iterative design process with practitioners, teachers and students of data science and visualization, resulting six types of cheat sheet (anatomy, construction, visual patterns, pitfalls, false-friends and well-known relatives) for six types of visualization, and formats for presentation. We assess these with a qualitative user study using 11 participants that demonstrates the readability and usefulness of our cheat sheets.

Learn with Haptics: Improving Vocabulary Recall with Free-form Digital Annotation on Touchscreen Mobiles

Mobile vocabulary learning interfaces typically present material only in auditory and visual channels, underutilizing the haptic modality. We explored haptic-integrated learning by adding free-form digital annotation to mobile vocabulary learning interfaces. Through a series of pilot studies, we identified three design factors: annotation mode, presentation sequence, and vibrotactile feedback, that influence recall in haptic-integrated vocabulary interfaces. These factors were then evaluated in a within-subject comparative study using a digital flashcard interface as baseline. Results using a 84-item vocabulary showed that the 'whole word' annotation mode is highly effective, yielding a 24.21% increase in immediate recall scores and a 30.36% increase in the 7-day delayed scores. Effects of presentation sequence and vibrotactile feedback were more transient; they affected the results of immediate tests, but not the delayed tests. We discuss the implications of these factors for designing future mobile learning applications.

Guess the Data: Data Work to Understand How People Make Sense of and Use Simple Sensor Data from Homes

Simple smart home sensors, e.g. for temperature or light, increasingly collect seemingly inconspicuous data. Prior work has shown that human sensemaking of such sensor data can reveal domestic activities. Such sensemaking presents an opportunity to empower people to understand the implications of simple smart home sensors. To investigate, we developed and field-tested the Guess the Data method, which enabled people to use and make sense of live data from their homes and to collectively interpret and reflect on anonymized data from the homes in our study. Our findings show how participants reconstruct behavior, both individually and collectively, expose the sensitive personal data of others, and use sensor data as evidence and for lateral surveillance within the household. We discuss the potential of our method as a participatory HCI method for investigating design of the IoT and implications created by doing data work on home sensors.

Please Call the Specialism: Using WeChat to Support Patient Care in China

We examine how WeChat has been adopted to support nurse-patient communication in an IVF clinic in China. In this setting, the biggest challenge to delivering high-quality patient-centred care is the large number of patients. Nurses typically spend less than five minutes with each patient during clinical visits. To compensate for such minimal in-person consultation, nurse-facilitated patient groups were created on WeChat, to extend medical care and facilitate peer support. Through an ethnographic study, we examined how these groups fit into the clinic's communication ecosystem, and the challenges they raise for nurse-facilitators who receive thousands of messages daily. We propose a set of design suggestions aiming to make the work of the nurse-facilitator easier and more effective. In highlighting the opportunities and challenges of using chat to extend care beyond the clinic, we contribute to a burgeoning discussion of how chat can support patient care in the Global South.

Monsters, Metaphors, and Machine Learning

Machine learning (ML) poses complex challenges for user experience (UX) designers. Typically unpredictable and opaque, it may produce unforeseen outcomes detrimental to particular groups or individuals, yet simultaneously promise amazing breakthroughs in areas as diverse as medical diagnosis and universal translation. This results in a polarized view of ML, which is often manifested through a technology-as-monster metaphor. In this paper, we acknowledge the power and potential of this metaphor by resurfacing historic complexities in human-monster relations. We (re)introduce these liminal and ambiguous creatures, and discuss their relation to ML. We offer a background to designers' use of metaphor, and show how the technology-as-monster metaphor can generatively probe and (re)frame the questions ML poses. We illustrate the effectiveness of this approach through a detailed discussion of an early-stage generative design workshop inquiring into ML approaches to supporting student mental health and well-being.

Collective Support and Independent Learning with a Voice-Based Literacy Technology in Rural Communities

Access to literacy is critical to children's futures, but formal education may be insufficient for fostering early literacy, especially in low-resource contexts. Educational technologies used at home may be able to help, but it is unclear whether or how children (and families) will use such technologies at home in rural communities, particularly in low-literate families. In this paper, we investigate these questions with a voice-based literacy technology deployed with families in 8 rural communities in Côte d'Ivoire for 4 months. We use interviews and observations with 37 families to investigate motivations, methods, and barriers for rural families' engagement with a literacy technology accessible via feature phones. We contribute insights into how families view digital literacy as a learning goal, leverage networks of supporters, and over time, transition from explicit to implicit support for children's learning.

The TA Framework: Designing Real-time Teaching Augmentation for K-12 Classrooms

Recently, the HCI community has seen increased interest in the design of teaching augmentation (TA): tools that extend and complement teachers' pedagogical abilities during ongoing classroom activities. Examples of TA systems are emerging across multiple disciplines, taking various forms: e.g., ambient displays, wearables, or learning analytics dashboards. However, these diverse examples have not been analyzed together to derive more fundamental insights into the design of teaching augmentation. Addressing this opportunity, we broadly synthesize existing cases to propose the TA framework. Our framework specifies a rich design space in five dimensions, to support the design and analysis of teaching augmentation. We contextualize the framework using existing designs cases, to surface underlying design trade-offs: for example, balancing actionability of presented information with teachers' needs for professional autonomy, or balancing unobtrusiveness with informativeness in the design of TA systems. Applying the TA framework, we identify opportunities for future research and design.

"We have been magnified for years - Now you are under the microscope!": Co-researchers with Learning Disabilities Created an Online Survey to Challenge Public Understanding of Learning Disabilities

Public attitudes towards learning disabilities (LDs) are generally reported as positive, inclusive and empathetic. However, these findings do not reflect the lived experiences of people with LDs. To shed light on this disparity, a team of co-researchers with LDs created the first online survey to challenge public understanding of LDs, asking questions in ways that are important to them and represent how they see themselves. Here, we describe and evaluate the process of creating an accessible survey platform and an online survey in a research team consisting of academic and non-academic professionals with and without LDs or autism. Through this inclusive research process, the co-designed survey met the expectations of the co-researchers and was well-received by the initial survey respondents. We reflect on the co-researchers' perspectives following the study completion, and consider the difficulties and advantages we encountered deploying such approaches and their potential implications on future survey data analysis.

Beyond Team Makeup: Diversity in Teams Predicts Valued Outcomes in Computer-Mediated Collaborations

In an increasingly globalized and service-oriented economy, people need to engage in computer-mediated collaborative problem solving (CPS) with diverse teams. However, teams routinely fail to live up to expectations, showcasing the need for technologies that help develop effective collaboration skills. We take a step in this direction by investigating how different dimensions of team diversity (demographic, personality, attitudes towards teamwork, prior domain experience) predict objective (e.g. effective solutions) and subjective (e.g. positive perceptions) collaborative outcomes. We collected data from 96 triads who engaged in a 30-minute CPS task via videoconferencing. We found that demographic diversity and differing attitudes towards teamwork predicted impressions of positive engagement, while personality diversity predicted learning outcomes. Importantly, these relationships were maintained after accounting for team makeup. None of the diversity measures predicted task performance. We discuss how our findings can be incorporated into technologies that aim to help diverse teams develop CPS skills.

Defining Haptic Experience: Foundations for Understanding, Communicating, and Evaluating HX

Haptic technology is maturing, with expectations and evidence that it will contribute to user experience (UX). However, we have very little understanding about how haptic technology can influence people's experience. Researchers and designers need a way to understand, communicate, and evaluate haptic technology's effect on UX. From a literature review and two studies - one with haptics novices, the other with expert hapticians - we developed a theoretical model of the factors that constitute a good haptic experience (HX). We define HX and propose its constituent factors: design parameters of Timeliness, Density, Intensity, and Timbre; the cross-cutting concern of Personalization; usability requirements of Utility, Causality, Consistency, and Saliency; and experiential factors of Harmony, Expressivity, Autotelics, Immersion, and Realism as guiding constructs important for haptic experience. This model will help guide design and research of haptic systems, inform language around haptics, and provide the basis for evaluative instruments, such as checklists, heuristics, or questionnaires.

MaraVis: Representation and Coordinated Intervention of Medical Encounters in Urban Marathon

There is an increased use of Internet-of-Things and wearable sensing devices in the urban marathon to ensure effective response to unforeseen medical needs. However, the massive amount of real-time, heterogeneous movement and psychological data of runners impose great challenges on prompt medical incident analysis and intervention. Conventional approaches compile such data into one dashboard visualization to facilitate rapid data absorption but fail to support joint decision-making and operations in medical encounters. In this paper, we present MaraVis, a real-time urban marathon visualization and coordinated intervention system. It first visually summarizes real-time marathon data to facilitate the detection and exploration of possible anomalous events. Then, it calculates an optimal camera route with an arrangement of shots to guide offline effort to catch these events in time with a smooth view transition. We conduct a within-subjects study with two baseline systems to assess the efficacy of MaraVis.

Emotional Footprints of Email Interruptions

Working in an environment with constant interruptions is known to affect stress, but how do interruptions affect emotional expression? Emotional expression can have significant impact on interactions among coworkers. We analyzed the video of 26 participants who performed an essay task in a laboratory while receiving either continual email interruptions or receiving a single batch of email. Facial videos of the participants were run through a convolutional neural network to determine the emotional mix via decoding of facial expressions. Using a novel co-occurrence matrix analysis, we showed that with batched email, a neutral emotional state is dominant with sadness being a distant second, and with continual interruptions, this pattern is reversed, and sadness is mixed with fear. We discuss the implications of these results for how interruptions can impact employees' well-being and organizational climate.

Nationality and Gender Biases in Multicultural Online Learning Environments: The Effects of Anonymity

Online learning environments eliminate geographical barriers and enable new forms of collaboration between students at large scale. Self-presentation within such environments affects how students interact with learning content and with each other. We explore how anonymity/identifiability in user profile design impacts student interactions in a large multicultural classroom across two geographical locations. After triangulating 150,000 online interactions with questionnaires and focus groups, we provide three major findings. First, being identifiable had a significant impact on how students accessed and rated content created by their peers. Second, when identifiable, cultural differences became more prominent, leading some students to avoid content created by classmates of certain nationalities. Finally, when students interacted with their real identities, there were significant and negative gender effects which were absent when students were anonymous. These findings contribute to our understanding of social dynamics within multicultural learning environments, and raise practical implications for tool design.

Designing for Employee Voice

Employee voice and workplace democracy have a positive impact on employee wellbeing and the performance of organizations. In this paper, we conducted interviews with employees to identify facilitators and inhibitors for voice within the workplace and a corresponding set of appropriate qualities: Civility, Validity, Safety and Egalitarianism. We then operationalised these qualities as a set of design goals - Assured Anonymity, Constructive Moderation, Adequate Slowness and Controlled Access - in the design and development of a secure anonymous employee voice system. Our novel take on the Enterprise Social Network aims to foster good citizenship whilst also promoting frank yet constructive discussion. We reflect on a two-week deployment of our system, the diverse range of candid discussions that emerged around important workplace issues and the potential for change within the host organization. We conclude by reflecting on the ways in which our approach shaped discourse and supported the creation of a trusted environment for employee voice.

Supporting Software Developers' Focused Work on Window-Based Desktops

Software developers, like other information workers, continuously switch tasks and applications to complete their work on their computer. Given the high fragmentation and complexity of their work, staying focused on the relevant pieces of information can become quite challenging in today's window-based environments, especially with the ever increasing monitor screen-size. To support developers in staying focused, we conducted a formative study with 18 professionals in which we examined their computer based and eye-gaze interaction with the window environment and devised a relevance model of open windows. Based on the results, we developed a prototype to dim irrelevant windows and reduce distractions, and evaluated it in a user study. Our results indicate that our model was able to predict relevant open windows with high accuracy and participants felt that integrating visual prominence into the desktop environment reduces clutter and distraction, which results in reduced window switching and an increase in focus.

MoveVR: Enabling Multiform Force Feedback in Virtual Reality using Household Cleaning Robot

Haptic feedback can significantly enhance the realism and immersiveness of virtual reality (VR) systems. In this paper, we propose MoveVR, a technique that enables realistic, multiform force feedback in VR leveraging commonplace cleaning robots. MoveVR can generate tension, resistance, impact and material rigidity force feedback with multiple levels of force intensity and directions. This is achieved by changing the robot's moving speed, rotation, position as well as the carried proxies. We demonstrated the feasibility and effectiveness of MoveVR through interactive VR gaming. In our quantitative and qualitative evaluation studies, participants found that MoveVR provides more realistic and enjoyable user experience when compared to commercially available haptic solutions such as vibrotactile haptic systems.

Between Scripts and Applications: Computational Media for the Frontier of Nanoscience

The popularity of computational notebooks heralds a return of software as computational media rather than turn-key applications. We believe this software model has potential beyond supporting just the computationally literate. We studied a biomolecular nano-design lab that works on a current frontier of science - RNA origami - whose researchers depend on computational tools to do their work, yet are not trained as programmers. Using a participatory design process, we developed a computational labbook to concretise what computational media could look like, using the principles of computability, malleability, shareability, and distributability suggested by previous work. We used this prototype to co-reflect with the nanoscientists about how it could transform their practice. We report on the computational culture specific to this research area; the scientists' struggles managing their computational environments; and their subsequent disempowerment yet dependence. Lastly, we discuss the generative potential and limitations of the four design principles for the future of computational media.

Brainsourcing: Crowdsourcing Recognition Tasks via Collaborative Brain-Computer Interfacing

This paper introduces brainsourcing: utilizing brain responses of a group of human contributors each performing a recognition task to determine classes of stimuli. We investigate to what extent it is possible to infer reliable class labels using data collected utilizing electroencephalography (EEG) from participants given a set of common stimuli. An experiment (N=30) measuring EEG responses to visual features of faces (gender, hair color, age, smile) revealed an improved F1 score of 0.94 for a crowd of twelve participants compared to an F1 score of 0.67 derived from individual participants and a random chance of 0.50. Our results demonstrate the methodological and pragmatic feasibility of brainsourcing in labeling tasks and opens avenues for more general applications using brain-computer interfacing in a crowdsourced setting.

Mixed Reality Light Fields for Interactive Remote Assistance

Remote assistance represents an important use case for mixed reality. With the rise of handheld and wearable devices, remote assistance has become practical in the wild. However, spontaneous provisioning of remote assistance requires an easy, fast and robust approach for capturing and sharing of unprepared environments. In this work, we make a case for utilizing interactive light fields for remote assistance. We demonstrate the advantages of object representation using light fields over conventional geometric reconstruction. Moreover, we introduce an interaction method for quickly annotating light fields in 3D space without requiring surface geometry to anchor annotations. We present results from a user study demonstrating the effectiveness of our interaction techniques, and we provide feedback on the usability of our overall system.

Expert Discussions Improve Comprehension of Difficult Cases in Medical Image Assessment

Medical data labeling workflows critically depend on accurate assessments from human experts. Yet human assessments can vary markedly, even among medical experts. Prior research has demonstrated benefits of labeler training on performance. Here we utilized two types of labeler training feedback: highlighting incorrect labels for difficult cases ("individual performance" feedback), and expert discussions from adjudication of these cases. We presented ten generalist eye care professionals with either individual performance alone, or individual performance and expert discussions from specialists. Compared to performance feedback alone, seeing expert discussions significantly improved generalists' understanding of the rationale behind the correct diagnosis while motivating changes in their own labeling approach; and also significantly improved average accuracy on one of four pathologies in a held-out test set. This work suggests that image adjudication may provide benefits beyond developing trusted consensus labels, and that exposure to specialist discussions can be an effective training intervention for medical diagnosis.

Collaborative Technologies for Children with Special Needs: A Systematic Literature Review

This paper presents a systematic literature review on collaborative technologies for children with special needs in ACM Digital Library. The aim of the review is to (1) reveal the current state of the art, (2) identify the types of technologies and contexts of use, the demographics and special needs of the target group, and the methodological approaches and theoretical groundings, and (3) define a future research agenda. The results of the systematic literature review show that collaborative technologies for children with special needs are increasingly gaining attention, mostly involve tangible and/or embodied interaction, and are often developed for use in the classroom. The target group that is most represented are boys between 6 to 12 years with Autism Spectrum Disorder. The results further show a wide range of evaluation criteria for measuring collaboration, an interchanging use of theoretical concepts and a lack of definitions for the concept collaboration, and a need for more demographically diverse studies.

Miniature Haptics: Experiencing Haptic Feedback through Hand-based and Embodied Avatars

We present Miniature Haptics, a new approach to providing realistic haptic experiences by applying miniaturized haptic feedback to hand-based, embodied avatars. By shrinking haptics to a much smaller scale, Miniature Haptics enables the exploration of new haptic experiences that are not practical to create at the full, human-body scale. Using Finger Walking in Place (FWIP) as an example avatar embodiment and control method, we first explored the feasibility of Miniature Haptics then conducted a human factors study to understand how people map their full-body skeletal model to their hands. To understand the user experience of Miniature Haptic, we developed a miniature football haptic display, and results from our user study show that Miniature Haptics significantly improved the realism and enjoyment of the experience and is preferred by users (p < 0.05). In addition, we present two miniature motion platforms supporting the haptic experiences of: 1) rapidly changing ground height for platform jumping games such as Super Mario Bros and 2) changing terrain slope. Overall, Miniature Haptics makes it possible to explore novel haptic experiences that have not been practical before.

Digital Juries: A Civics-Oriented Approach to Platform Governance

As concerns have grown regarding harmful content spread on social media, platform mechanisms for content moderation have become increasingly significant. However, many existing platform governance structures lack formal processes for democratic participation by users of the platform. Drawing inspiration from constitutional jury trials in many legal systems, this paper proposes digital juries as a civics-oriented approach for adjudicating content moderation cases. Building on existing theoretical models of jury decision-making, we outline a 5-stage model characterizing the space of design considerations in a digital jury process. We implement two examples of jury designs involving blind-voting and deliberation. From users who participate in our jury implementations, we gather informed judgments of the democratic legitimacy of a jury process for content moderation. We find that digital juries are perceived as more procedurally just than existing common platform moderation practices, but also find disagreement over whether jury decisions should be enforced or used as recommendations.

Patriarchy, Maternal Health and Spiritual Healing: Designing Maternal Health Interventions in Pakistan

We examine the opportunities and challenges in designing for maternal health in low-income, low-resource communities in patriarchal and religious contexts. Pakistan faces a crisis in maternal health with a maternal mortality ratio of 178 deaths per 100,000 live births, as compared to the developed-country average of just 12 deaths per 100,000. Through a 6-month long qualitative, empirical study we examine the prevalent beliefs and practices around maternal health in Pakistan, the access women have to health-care, the existing religious practices that influence them and the agency they exert in their own health-care decision making. We reveal the rampant misinformation among mothers and health workers, house-hold power dynamics that impact maternal health and the deep link between maternal health and religious beliefs. We also show how current maternal health care interventions fit poorly into this context and discuss alternate design recommendations for meeting the maternal health needs of these women.

BrailleBlocks: Computational Braille Toys for Collaborative Learning

Braille literacy has fallen in recent years, and many blind children now grow up without learning Braille. However, learning Braille can increase employment chances and improve literacy skills. We introduce BrailleBlocks, a system to help visually impaired children learn and practice Braille alongside a sighted parent. BrailleBlocks comprises a set of tangible blocks and pegs, each block representing a Braille cell, and an associated application with games. The system automatically tracks and recognizes the blocks so that parents can follow along even if they cannot read Braille. We conducted a user study to test BrailleBlocks with five families, with five parents and six visually impaired children. The contributions of this work are a novel approach to Braille education toys, observations of how visually impaired children and sighted parents used this system together, their insights on current issues with Braille educational tools, and actionable feedback for future Braille-based learning tools.

Investigating the Necessity of Delay in Marking Menu Invocation

Delayed display of menu items is a core design component of marking menus, arguably to prevent visual distraction and foster the use of mark mode. We investigate these assumptions, by contrasting the original marking menu design with immediately-displayed marking menus. In three controlled experiments, we fail to reveal obvious and systematic performance or usability advantages to using delay and mark mode. Only in very constrained settings – after significant training and only two items to learn – did traditional marking menus show a time improvement of about 260~ms. Otherwise, we found an overall decrease in performance with delay, whether participants exhibited practiced or unpracticed behaviour. Our final study failed to demonstrate that an immediately-displayed menu interface is more visually disrupting than a delayed menu. These findings inform the costs and benefits of incorporating delay in marking menus, and motivate guidelines for situations in which its use is desirable.

GoTree: A Grammar of Tree Visualizations

We present GoTree, a declarative grammar allowing users to instantiate tree visualizations by specifying three aspects: visual elements, layout, and coordinate system. Within the set of all possible tree visualization techniques, we identify a subset of techniques that are both "unit-decomposable" and "axis-decomposable" (terms we define). For tree visualizations within this subset, GoTree gives the user flexible and fine-grained control over the parameters of the techniques, supporting both explicit and implicit tree visualizations. We developed Tree Illustrator, an interactive authoring tool based on GoTree grammar. Tree Illustrator allows users to create a considerable number of tree visualizations, including not only existing techniques but also undiscovered and hybrid visualizations. We demonstrate the expressiveness and generative power of GoTree with a gallery of examples and conduct a qualitative study to validate the usability of Tree Illustrator.

Measuring Identity Confusion with Uniform Resource Locators

Uniform Resource Locators (URLs) unambiguously specify host identity on the web. URLs are syntactically complex, and although software can accurately parse identity from URLs, users are frequently exposed to URLs and expected to do the same. Unfortunately, incorrect assessment of identity from a URL can expose users to attacks, such as typosquatting and phishing. Our work studies how well users can correctly determine the host identity of real URLs from common services and obfuscated "look-alike" URLs. We observe that participants employ a wide range of URL parsing strategies, and can identify real URLs 93% of time. However, only 40% of obfuscated URLs were identified correctly. These mistakes highlighted several ways in which URLs were confusing to users and why their existing URL parsing strategies fall short. We conclude with future research directions for reliably conveying website identity to users.

Understanding Older Adults' Participation in Design Workshops

Design workshops are a popular means of including older adults in technology development. However, there are open questions around how to best scaffold this participation, particularly in supporting older adults to associate their designs with themselves, rather than designing for an "other older adult." By conducting workshops focusing on envisioning the future of internet of things (IoT) technologies at home, we provide an understanding of how older individuals participate in group activities to conceptualize technology for themselves. We find that at different stages of the design process, individuals shift in who they envision the end user of the technology: at first, they think about common older adult needs, then turn to designing for themselves. Individuals' attitudes towards technology also impact group dynamics along with final design ideas. Our discussion contributes to an understanding of how to support older adults in designing for themselves, new perspectives on aging-in-place technologies, and recommendations for configuring design workshops with older individuals.

Is Too Much System Caution Counterproductive? Effects of Varying Sensitivity and Automation Levels in Vehicle Collision Avoidance Systems

Autonomous vehicle system performance is limited by uncertainties inherent in the driving environment and challenges in processing sensor data. Engineers thus face the design decision of biasing systems toward lower sensitivity to potential threats (more misses) or higher sensitivity (more false alarms). We explored this problem for Automatic Emergency Braking systems in Level 3 autonomous vehicles, where the driver is required to monitor the system for failures. Participants (N=48) drove through a simulated suburban environment and experienced detection misses, perfect performance, or false alarms. We found that driver vigilance was greater for less-sensitive braking systems, resulting in improved performance during a potentially fatal failure. In addition, regardless of system bias, greater levels of autonomy resulted in significantly worse driver performance. Our results demonstrate that accounting for the effects of system bias on driver vigilance and performance will be critical design considerations as vehicle autonomy levels increase.

Re-examining Whether, Why, and How Human-AI Interaction Is Uniquely Difficult to Design

Artificial Intelligence (AI) plays an increasingly important role in improving HCI and user experience. Yet many challenges persist in designing and innovating valuable human-AI interactions. For example, AI systems can make unpredictable errors, and these errors damage UX and even lead to undesired societal impact. However, HCI routinely grapples with complex technologies and mitigates their unintended consequences. What makes AI different? What makes human-AI interaction appear particularly difficult to design? This paper investigates these questions. We synthesize prior research, our own design and research experience, and our observations when teaching human-AI interaction. We identify two sources of AI's distinctive design challenges: 1) uncertainty surrounding AI's capabilities, 2) AI's output complexity, spanning from simple to adaptive complex. We identify four levels of AI systems. On each level, designers encounter a different subset of the design challenges. We demonstrate how these findings reveal new insights for designers, researchers, and design tool makers in productively addressing the challenges of human-AI interaction going forward.

Designing IoT Resources to Support Outdoor Play for Children

We describe a Research-through-Design (RtD) project that explores the Internet of Things (IoT) as a resource for children's free play outdoors. Based on initial insights from a design ethnography, we developed four RtD prototypes for social play in different scenarios of use outdoors, including congregating on a street or in a park to play physical games with IoT. We observed these prototypes in use by children in their free play in two community settings, and report on the qualitative analysis of our fieldwork. Our findings highlight the designs' material qualities that encouraged social and physical play under certain conditions, suggesting social affordances that are central to the success of IoT designs for free play outdoors. We provide directions for future research that addresses the challenges faced when deploying IoT with children, contributing new considerations for interaction design with children in outdoor settings and free play contexts.

Knock on Wood: Combining Redirected Touching and Physical Props for Tool-Based Interaction in Virtual Reality

When physical props serve as proxies for virtual tools used to manipulate the virtual environment, it is challenging to provide appropriate haptic feedback. Redirected tool-mediated manipulation addresses this challenge by distorting the mapping between physical and virtual tools to provide a sensation of manipulating the virtual environment, when the physical tool comes into contact with another physical prop. For example, a virtual hammer's position can be offset to ensure that physical impacts accompany each strike of a virtual nail. We demonstrate the idea by showing that it can be used to create sensations of impact and resistance when driving a virtual nail into a surface, when tightening a virtual screw, and when sawing through a virtual plank. The results of a user study indicate that the proposed approach is perceived as more realistic than interaction with a single physical prop or controller and no notable detriments to precision were observed.

Wearable Microphone Jamming

We engineered a wearable microphone jammer that is capable of disabling microphones in its user's surroundings, including hidden microphones. Our device is based on a recent exploit that leverages the fact that when exposed to ultrasonic noise, commodity microphones will leak the noise into the audible range.

Unfortunately, ultrasonic jammers are built from multiple transducers and therefore exhibit blind spots, i.e., locations in which transducers destructively interfere and where a microphone cannot be jammed. To solve this, our device exploits a synergy between ultrasonic jamming and the naturally occur- ring movements that users induce on their wearable devices (e.g., bracelets) as they gesture or walk. We demonstrate that these movements can blur jamming blind spots and increase jamming coverage. Moreover, current jammers are also directional, requiring users to point the jammer to a microphone; instead, our wearable bracelet is built in a ring-layout that al- lows it to jam in multiple directions. This is beneficial in that it allows our jammer to protect against microphones hidden out of sight.

We evaluated our jammer in a series of experiments and found that: (1) it jams in all directions, e.g., our device jams over 87% of the words uttered around it in any direction, while existing devices jam only 30% when not pointed directly at the microphone; (2) it exhibits significantly less blind spots; and, (3) our device induced a feeling of privacy to participants of our user study. We believe our wearable provides stronger privacy in a world in which most devices are constantly eavesdropping on our conversations.

Embroidered Resistive Pressure Sensors: A Novel Approach for Textile Interfaces

We present a novel method for augmenting arbitrary fabrics with textile-based pressure sensors using an off-the-shelf embroidery machine. We apply resistive textiles and conductive yarns on top of a base fabric, to yield a flexible and versatile continuous sensing device, which is based on the widespread principle of force sensitive resistors. The patches can easily be attached to measurement and/or computing devices, e.g. for controlling accessories. In this paper, we investigate the impacts of related design and fabrication parameters, introduce five different pattern designs, and discuss their pros and cons. We present crucial insights and recommendations for design and manufacturing of embroidered pressure sensors. Our sensors show a very low activation threshold, as well as good dynamic range, signal-to-noise ratio, and part-to-part repeatability.

BiTipText: Bimanual Eyes-Free Text Entry on a Fingertip Keyboard

We present a bimanual text input method on a miniature fingertip keyboard, that invisibly resides on the first segment of a user's index finger on both hands. Text entry can be carried out using the thumb-tip to tap the tip of the index finger. The design of our keyboard layout followed an iterative process, where we first conducted a study to understand the natural expectation of the handedness of the keys in a QWERTY layout for users. Among a choice of 67,108,864 design variations, we identified 1295 candidates offering a good satisfaction for user expectations. Based on these results, we computed an optimized bimanual keyboard layout, while considering the joint optimization problems of word ambiguity and movement time. Our user evaluation revealed that participants achieved an average text entry speed of 23.4 WPM.

The Critical Catalog: Library Information Systems, Tricksterism, and Social Justice

In this paper, we describe the Critical Catalog, a grant-funded research through design project intended to investigate metadata elements, values, and organizational structures necessary to intentionally advocate for diversity and expose library users to resources from populations traditionally marginalized in literature and publishing. Drawing on principles from critical design, the prototype functions as a critical intervention intended to raise questions and stimulate debate, rather than a purely technical fix to deeply social concerns. A detailed reflective discussion of the design process reveals how existing infrastructural constraints shaped design decisions that led to increased advocacy and a stronger activist standpoint. We discuss the use of metadata as design material for social justice, the application of tricksterism in HCI, and how both practical limitations from professional contexts and imposed limitations based on identities and positions of power can lead to surprising places, meanings, and questions.

"My Library Has Just Been Obliterated": Producing New Norms of Use Via Software Update

Software updates are commonly perceived as tools for fixing flaws and improving functionality. In this paper, we problematise this view by showing how software updates may also be used by vendors to create new norms of use that control user behaviour and reduce their agency. We explore the nature and aftermath of a controversial software update that was released by Spotify in June 2019. By analysing almost 3,500 reactions to this update, we show how it removed and modified several features in ways that severely affected users' capability to organise, navigate, and maintain their music libraries, while it pushed modes of listening that delegate song selection to Spotify. Elaborating upon our results, we discuss how updates may be used as political tools that privilege certain forms of behaviour while restricting others. We also portray updates as sites where ongoing struggles and negotiations regarding user agency and digital ownership take place.

"Energy is a Finite Resource": Designing Technology to Support Individuals across Fluctuating Symptoms of Depression

While the HCI field increasingly examines how digital tools can support individuals in managing mental health conditions, it remains unclear how these tools can accommodate these conditions' temporal aspects. Based on weekly interviews with five individuals with depression, conducted over six weeks, this study identifies design opportunities and challenges related to extending technology-based support across fluctuating symptoms. Our findings suggest that participants perceive events and contexts in daily life to have marked impact on their symptoms. Results also illustrate that ebbs and flows in symptoms profoundly affect how individuals practice depression self-management. While digital tools often aim to reach individuals while they feel depressed, we suggest they should also engage individuals when they are less symptomatic, leveraging their energy and motivation to build habits, establish plans and goals, and generate and organize content to prepare for symptom onset.

An Honest Conversation: Transparently Combining Machine and Human Speech Assistance in Public Spaces

There is widespread concern over the ways speech assistant providers currently use humans to listen to users' queries without their knowledge. We report two iterations of the TalkBack smart speaker, which transparently combines machine and human assistance. In the first, we created a prototype to investigate whether people would choose to forward their questions to a human answerer if the machine was unable to help. Longitudinal deployment revealed that most users would do so when given the explicit choice. In the second iteration we extended the prototype to draw upon spoken answers from previous deployments, combining machine efficiency with human richness. Deployment of this second iteration shows that this corpus can help provide relevant, human-created instant responses. We distil lessons learned for those developing conversational agents or other AI-infused systems about how to appropriately enlist human-in-the-loop information services to benefit users, task workers and system performance.

Social Boundaries for Personal Agents in the Interpersonal Space of the Home

The presence of voice activated personal assistants (VAPAs) in people's homes rises each year [31]. Industry efforts are invested in making interactions with VAPAs more personal by leveraging information from messages and calendars, and by accessing user accounts for 3rd party services. However, the use of personal data becomes more complicated in interpersonal spaces, such as people's homes. Should a shared agent access the information of many users? If it does, how should it navigate issues of privacy and control? Designers currently lack guidelines to help them design appropriate agent behaviors. We used Speed Dating to explore inchoate social mores around agent actions within a home, including issues of proactivity, interpersonal conflict, and agent prevarication. Findings offer new insights on how more socially sophisticated agents might sense, make judgements about, and navigate social roles and individuals. We discuss how our findings might impact future research and future agent behaviors.

A Change of Perspective: How User Orientation Influences the Perception of Physicalizations

As physicalizations encode data in their physical 3D form, the orientation in which the user is viewing the physicalization may impact the way the information is perceived. However, this relation between user orientation and perception of physical properties is not well understood or studied. To investigate this relation, we conducted an experimental study with 20 participants who viewed 6 exemplars of physicalizations from 4 different perspectives. Our findings show that perception is directly influenced by user orientation as it affects (i) the number and type of clusters, (ii) anomalies and (iii) extreme values identified within a physicalization. Our results highlight the complexity and variability of the relation between user orientation and perception of physicalizations.

Gripmarks: Using Hand Grips to Transform In-Hand Objects into Mixed Reality Input

We introduce Gripmarks, a system that enables users to opportunistically use objects they are already holding as input surfaces for mixed reality head-mounted displays (HMD). Leveraging handheld objects reduces the need for users to free up their hands or acquire a controller to interact with their HMD. Gripmarks associate a particular hand grip with the shape primitive of the physical object without the need of object recognition or instrumenting the object. From the grip pose and shape primitive we can infer the surface of the object. With an activation gesture, we can enable the object for use as input to the HMD. With five gripmarks we demonstrate a recognition rate of 94.2%; we show that our grip detection benefits from the physical constraints of holding an object. We explore two categories of input objects 1) tangible surfaces and 2) tangible tools and present two representative applications. We discuss the design and technical challenges for expanding the concept.

The Upcycled Home: Removing Barriers to Lightweight Modification of the Home's Everyday Objects

The Internet-of-things (IoT) embeds computing in everyday objects, but has largely focused on new devices while ignoring the home's many existing possessions. We present a field study with 10 American families to understand how these possessions could be included in the smart home through upcycling. We describe three patterns for how families collaborate around home responsibilities; we explore families' mental models of home that may be in tension with existing IoT systems; and we identify ways that families can more easily imagine a smart home that includes their existing possessions. These insights can help us design an upcycled approach to IoT that supports users in reconfiguring objects (and social roles as mediated by objects) in a way that is sensitive to what will be displaced, discarded, or made obsolete. Our findings inform the design of future lightweight systems for the upcycled home.

Adhering, Steering, and Queering: Treatment of Gender in Natural Language Generation

Natural Language Generation (NLG) supports the creation of personalized, contextualized, and targeted content. However, the algorithms underpinning NLG have come under scrutiny for reinforcing gender, racial, and other problematic biases. Recent research in NLG seeks to remove these biases through principles of fairness and privacy. Drawing on gender and queer theories from sociology and Science and Technology studies, we consider how NLG can contribute towards the advancement of gender equity in society. We propose a conceptual framework and technical parameters for aligning NLG with feminist HCI qualities. We present three approaches: (1) adhering to current approaches of removing sensitive gender attributes, (2) steering gender differences away from the norm, and (3) queering gender by troubling stereotypes. We discuss the advantages and limitations of these approaches across three hypothetical scenarios; newspaper headlines, job advertisements, and chatbots. We conclude by discussing considerations for implementing this framework and related ethical and equity agendas.

Mental Models of AI Agents in a Cooperative Game Setting

As more and more forms of AI become prevalent, it becomes increasingly important to understand how people develop mental models of these systems. In this work we study people's mental models of AI in a cooperative word guessing game. We run think-aloud studies in which people play the game with an AI agent; through thematic analysis we identify features of the mental models developed by participants. In a large-scale study we have participants play the game with the AI agent online and use a post-game survey to probe their mental model. We find that those who win more often have better estimates of the AI agent's abilities. We present three components for modeling AI systems, propose that understanding the underlying technology is insufficient for developing appropriate conceptual models (analysis of behavior is also necessary), and suggest future work for studying the revision of mental models over time.

TAGSwipe: Touch Assisted Gaze Swipe for Text Entry

The conventional dwell-based methods for text entry by gaze are typically slow and uncomfortable. A swipe-based method that maps gaze path into words offers an alternative. However, it requires the user to explicitly indicate the beginning and ending of a word, which is typically achieved by tedious gaze-only selection. This paper introduces TAGSwipe, a bi-modal method that combines the simplicity of touch with the speed of gaze for swiping through a word. The result is an efficient and comfortable dwell-free text entry method. In the lab study TAGSwipe achieved an average text entry rate of 15.46 wpm and significantly outperformed conventional swipe-based and dwell-based methods in efficacy and user satisfaction.

Studying the Effects of Cognitive Biases in Evaluation of Conversational Agents

Humans quite frequently interact with conversational agents. The rapid advancement in generative language modeling through neural networks has helped advance the creation of intelligent conversational agents. Researchers typically evaluate the output of their models through crowdsourced judgments, but there are no established best practices for conducting such studies. Moreover, it is unclear if cognitive biases in decision-making are affecting crowdsourced workers' judgments when they undertake these tasks. To investigate, we conducted a between-subjects study with 77 crowdsourced workers to understand the role of cognitive biases, specifically anchoring bias, when humans are asked to evaluate the output of conversational agents. Our results provide insight into how best to evaluate conversational agents. We find increased consistency in ratings across two experimental conditions may be a result of anchoring bias. We also determine that external factors such as time and prior experience in similar tasks have effects on inter-rater consistency.

Personal Space in Play: Physical and Digital Boundaries in Large-Display Cooperative and Competitive Games

As multi-touch displays grow in size and shrink in price, they are more commonly used as gaming devices. When co-located users play games on a single, large display, establishing and maintaining their physical and digital territories poses a social challenge to their interaction. To gain insight into the mechanisms of establishing and maintaining users' physical and digital territories, we analyze territorial interactions in cooperative and competitive multiplayer gameplay. Participants reported weighing each game interaction based on perceived intent to determine how socially acceptable they deemed each behaviour. In light of our observations, we contribute and discuss implications for the design of multi-user, large display, co-located, touchscreen games that consider display properties, digital and physical space, permeability of boundaries, and asymmetry of play to create interactions between players.

"Hi! I am the Crowd Tasker" Crowdsourcing through Digital Voice Assistants

Inspired by the increasing prevalence of digital voice assistants, we demonstrate the feasibility of using voice interfaces to deploy and complete crowd tasks. We have developed Crowd Tasker, a novel system that delivers crowd tasks through a digital voice assistant. In a lab study, we validate our proof-of-concept and show that crowd task performance through a voice assistant is comparable to that of a web interface for voice-compatible and voice-based crowd tasks for native English speakers. We also report on a field study where participants used our system in their homes. We find that crowdsourcing through voice can provide greater flexibility to crowd workers by allowing them to work in brief sessions, enabling multi-tasking, and reducing the time and effort required to initiate tasks. We conclude by proposing a set of design guidelines for the creation of crowd tasks for voice and the development of future voice-based crowdsourcing systems.

Dark Patterns after the GDPR: Scraping Consent Pop-ups and Demonstrating their Influence

New consent management platforms (CMPs) have been introduced to the web to conform with the EU's General Data Protection Regulation, particularly its requirements for consent when companies collect and process users' personal data. This work analyses how the most prevalent CMP designs affect people's consent choices. We scraped the designs of the five most popular CMPs on the top 10,000 websites in the UK (n=680). We found that dark patterns and implied consent are ubiquitous; only 11.8% meet our minimal requirements based on European law. Second, we conducted a field experiment with 40 participants to investigate how the eight most common designs affect consent choices. We found that notification style (banner or barrier) has no effect; removing the opt-out button from the first page increases consent by 22-23 percentage points; and providing more granular controls on the first page decreases consent by 8-20 percentage points. This study provides an empirical basis for the necessary regulatory action to enforce the GDPR, in particular the possibility of focusing on the centralised, third-party CMP services as an effective way to increase compliance.

WithYou: Automated Adaptive Speech Tutoring With Context-Dependent Speech Recognition

Learning to speak in foreign languages is hard. Speech shadowing has been rising as a proven way to practice speaking, which asks a learner to listen and repeat a native speech template as simultaneously as possible. However, shadowing can be hard to do because learners can frequently fail to follow the speech and unintentionally interrupt a practice session. Worse, as a technical way to evaluate shadowing performance in real-time has not been established, no automated solutions are available to help. In this paper, we propose a technical framework with context-dependent speech recognition to evaluate shadowing in real-time. We propose a shadowing tutor system called WithYou, which can automatically adjust the playback and the difficulty of a speech template when learners fail, so shadowing becomes smooth and tailored. Results from a user study show that WithYou provides greater speech improvements (14%) than the conventional method (2.7%) with a lower cognitive load.

ThermalRing: Gesture and Tag Inputs Enabled by a Thermal Imaging Smart Ring

The heterogeneous and ubiquitous input demands in smart spaces call for an input device that can enable rich and spontaneous interactions. We propose ThermalRing, a thermal imaging smart ring using low-resolution thermal camera for identity-anonymous, illumination-invariant, and power-efficient sensing of both dynamic and static gestures. We also design ThermalTag, thin and passive thermal imageable tags that reflect the heat from the human hand. ThermalTag can be easily made and applied onto everyday objects by users. We develop sensing techniques for three typical input demands: drawing gestures for device pairing, click and slide gestures for device control, and tag scan gestures for quick access. The study results show that ThermalRing can recognize nine drawing gestures with an overall accuracy of 90.9%, detect click gestures with an accuracy of 94.9%, and identify among six ThermalTags with an overall accuracy of 95.0%. Finally, we show the versatility and potential of ThermalRing through various applications.

Predicting and Diagnosing User Engagement with Mobile UI Animation via a Data-Driven Approach

Animation, a common design element in user interfaces (UI), can impact user engagement (UE) with mobile applications. To avoid impairing UE due to improper design of animation, designers rely on resource-intensive evaluation methods like user studies or expert reviews. To alleviate this burden, we propose a data-driven approach to assisting designers in examining UE issues with their animation designs. We first crowdsource UE assessments of mobile UI animations. Based on the collected data, we then build a novel deep learning model that captures both spatial and temporal features of animations to predict their UE levels. Evaluations show that our model achieves a reasonable accuracy. We further leverage the animation feature encoded by our model and a sample set of expert reviews to derive potential UE issues of a particular animation. Finally, we develop a proof-of-concept tool and evaluate its potential usage in actual design practices with experts

Color and Animation Preferences for a Light Band eHMI in Interactions Between Automated Vehicles and Pedestrians

In this paper, we report user preferences regarding color and animation patterns to support the interaction between Automated Vehicles (AVs) and pedestrians through an external Human-Machine-Interface (eHMI). Existing concepts of eHMI differ -- among other things -- in their use of colors or animations to express an AV's yielding intention. In the absence of empirical research, there is a knowledge gap regarding which color and animation leads to highest usability and preferences in traffic negotiation situations. We conducted an online survey (N=400) to investigate the comprehensibility of a light band eHMI with a combination of 5 color and 3 animation patterns for a yielding AV. Results show that cyan is considered a neutral color for communicating a yielding intention. Additionally, a uniformly flashing or pulsing animation is preferred compared to any pattern that animates sideways. These insights can contribute in the future design and standardization of eHMIs.

A Participatory Simulation of the Accountable Capitalism Act

Interactive computing systems increasingly allow for experimental evaluations of fundamental issues in law, government, and society. In this paper, we describe a participatory simulation of the Accountable Capitalism Act, a bill proposed in 2018 by US Senator Elizabeth Warren. We present findings from an empirical study conducted using this system, relating to the impact of 1) interactive visualization and 2) the Accountable Capitalism Act legal framework on the behavior of participants acting as corporate directors. From this study, we draw lessons about research possibilities at the juncture of HCI and legal and policy studies. This study contributes an analysis and evaluation of a design probe used to investigate potential impacts of the Accountable Capitalism Act, experimental evidence from a study conducted using the design probe, and guidance for future participatory simulations that seek to inform the design of social institutions.

GUIComp: A GUI Design Assistant with Real-Time, Multi-Faceted Feedback

Users may face challenges while designing graphical user interfaces, due to a lack of relevant experience and guidance. This paper aims to investigate the issues users face during the design process, and how to resolve them. To this end, we conducted semi-structured interviews, based on which we built a GUI prototyping assistance tool called GUIComp. This tool can be connected to GUI design software as an extension, and it provides real-time, multi-faceted feedback on a user's current design. Additionally, we conducted two user studies, in which we asked participants to create mobile GUIs with or without GUIComp, and requested online workers to assess the created GUIs. The experimental results show that GUIComp facilitated iterative designs and the participants with GUIComp had better a user experience and produced more acceptable designs than those who did not use it.

Searching for Mental Health: A Mixed-Methods Study of Young People's Online Help-seeking

Seeking help is often an important step in addressing mental health difficulties. Evidence suggests that positive help-seeking experiences contribute to an increased likelihood of future help-seeking and achieving improved outcomes. However, help-seeking is a complex process. Alongside traditional sources, digital technologies offer many pathways to help. Using a mixed methods approach across two studies, this paper explores key design factors for online mental health resources that can support young people's help-seeking. First, a large online survey (n=1308) highlighted challenges and identified common help-seeking scenarios, including information-seeking, person-centred approaches and crisis situations. Using survey data, personas were developed to represent different help-seekers - each characterised by a particular help-seeking scenario. The personas were then used in co-design workshops to facilitate further exploration of help-seeking needs. Four key design considerations were identified: connectedness, accessible information, personalisation, and immediacy. Based on our findings, we provide design recommendations that are grounded in existing theories of help-seeking.

Culture in Action: Unpacking Capacities to Inform Assets-Based Design

The field of Human-Computer Interaction (HCI) aims at securing a lasting impact for technology-based interventions in the context of social inequities. Increasingly, HCI scholars are proposing assets-based design as an effective approach towards this issue. Rather than starting from people's needs and deficits, this approach posits that design should start from a deep understanding of people's assets. A pending issue, however, is how to account for the situated nature of assets; that is, how to decide which asset to leverage and for what design purpose. Drawing from cultural sociology and shifting the emphasis from assets to capacities, we propose Swidler's theory of culture-in-action as an analytical lens for unpacking the complex relationship between capacities, goals, and structural limitations. Leveraging findings from a Participatory Design engagement with 35 Latino immigrant parents for envisioning parent-education technologies, we demonstrate the applicability of this lens. We contribute to HCI scholarship by further discussing 1) how to analyze capacities' design potential, and 2) the methodological particularities for collecting them.

MRAT: The Mixed Reality Analytics Toolkit

Significant tool support exists for the development of mixed reality (MR) applications; however, there is a lack of tools for analyzing MR experiences. We elicit requirements for future tools through interviews with 8 university research, instructional, and media teams using AR/VR in a variety of domains. While we find a common need for capturing how users perform tasks in MR, the primary differences were in terms of heuristics and metrics relevant to each project. Particularly in the early project stages, teams were uncertain about what data should, and even could, be collected with MR technologies. We designed the Mixed Reality Analytics Toolkit (MRAT) to instrument MR apps via visual editors without programming and enable rapid data collection and filtering for visualizations of MR user sessions. With MRAT, we contribute flexible interaction tracking and task definition concepts, an extensible set of heuristic techniques and metrics to measure task success, and visual inspection tools with in-situ visualizations in MR. Focusing on a multi-user, cross-device MR crisis simulation and triage training app as a case study, we then show the benefits of using MRAT, not only for user testing of MR apps, but also performance tuning throughout the design process.

Investigating the Effects of Self-Avatars and Story-Relevant Avatars on Children's Creative Storytelling

Storytelling is a critical step in the cognitive development of children. Particularly, this requires children to mentally project into the story context and to identify with the thoughts of the characters in their stories. We propose to support free imagination in creative storytelling through an enactment-based approach that allows children to embody an avatar and perform as the story character. We designed our story creation interface with two modes of avatar: the story-relevant avatar and the self-avatar, to investigate the effects of avatar design on the quality of children's creative products. In our study with 20 child participants, the results indicate that self-avatars can create a stronger sense of identification and embodied presence, while story-relevant avatars can provide a scaffold for mental projection.

Restorative Play: Videogames Improve Player Wellbeing After a Need-Frustrating Event

People often use videogames to restore wellbeing after negative experiences in day-to-day life. Although some research suggests that play can restore wellbeing, few studies have investigated the means by which restoration occurs. We employed self-determination theory (SDT) to understand how and to what degree play improves wellbeing after a need-frustrating event, and how players understand experiences of competence in play. Sixty-five participants worked at a competence manipulation task prior to playing a competence-satisfying videogame. Competence, affect, and vitality improved during play, and in-game experiences of need frustration were observed to effectively predict post-play negative affect. Post-experiment interviews indicate that videogames are seen to support competence relative to perceived skill, extending our knowledge of how design can support competence and restoration. We demonstrate that play can restore wellbeing, present need frustration as a means to explain negative experiences with interactive systems, and discuss effects of design on competence.

PneuSleeve: In-fabric Multimodal Actuation and Sensing in a Soft, Compact, and Expressive Haptic Sleeve

Integration of soft haptic devices into garments can improve their usability and wearability for daily computing interactions. In this paper, we introduce PneuSleeve, a fabric-based, compact, and highly expressive forearm sleeve which can render a broad range of haptic stimuli including compression, skin stretch, and vibration. The haptic stimuli are generated by controlling pneumatic pressure inside embroidered stretchable tubes. The actuation configuration includes two compression actuators on the proximal and distal forearm, and four uniformly distributed linear actuators around and tangent to the forearm. Further, to ensure a suitable grip force, two soft mutual capacitance sensors are fabricated and integrated into the compression actuators, and a closed-loop force controller is implemented. We physically characterize the static and dynamic behavior of the actuators, as well as the performance of closed-loop control. We quantitatively evaluate the psychophysical characteristics of the six actuators in a set of user studies. Finally, we show the expressiveness of PneuSleeve by evaluating combined haptic stimuli using subjective assessments.

Teenage Visitor Experience: Classification of Behavioral Dynamics in Museums

Teenagers' engagement in museums is much talked about but little research has been done to understand their behavior and inform design. Findings from co-design sessions with teenagers suggested they value games and stories when thinking about enjoyable museum tours. Informed by these findings and working with a natural history museum, we designed: a story-based tour (Turning Point) and a game-based tour (Haunted Encounters), informed by similar content. The two strategies were evaluated with 78 teenagers (15-19 years old) visiting the museum as part of an educational school trip. We assessed teenagers' personality in class; qualitative and quantitative data on their engagement, experience, and usability of the apps were collected at the museum. The triangulation of quantitative and qualitative data show personality traits mapping into different behaviors. We offer implications for the design of museum apps targeted to teenagers, a group known as difficult to reach.

Vibrotactile Funneling Illusion and Localization Performance on the Head

The vibrotactile funneling illusion is the sensation of a single (non-existing) stimulus somewhere in-between the actual stimulus locations. Its occurrence depends upon body location, distance between the actuators, signal synchronization, and intensity. Related work has shown that the funneling illusion may occur on the forehead. We were able to reproduce these findings and explored five further regions to get a more complete picture of the occurrence of the funneling illusion on the head. The results of our study (24 participants) show that the actuator distance, for which the funneling illusion occurs, strongly depends upon the head region. Moreover, we evaluated the centralizing bias (smaller perceived than actual actuator distances) for different head regions, which also showed widely varying characteristics. We computed a detailed heat map of vibrotactile localization accuracies on the head. The results inform the design of future tactile head-mounted displays that aim to support the funneling illusion.

Modeling the Endpoint Uncertainty in Crossing-based Moving Target Selection

Modeling the endpoint uncertainty of moving target selection with crossing is essential to understand factors such as speed-accuracy trade-off and interaction efficiency in crossing-based user interfaces with dynamic contents. However, there have been few studies looking into this research topic in the HCI field. This paper presents a Quaternary-Gaussian model to quantitatively measure the endpoint uncertainty in crossing-based moving target selection. To validate this model, we conducted an experiment with discrete crossing tasks on five factors, i.e., initial distance, size, speed, orientation, and moving direction. Results showed that our model fit the data of μ and σ accurately with adjusted R2 of 0.883 and 0.920. We also demonstrated the validity of our model in predicting error rates in crossing-based moving target selection. We concluded with a set of implications for future designs.

"I Feel Like This is a Bad Thing": Investigating Disassembly in Action for Novices

Materials are dynamic-they can be shaped and changed. Often however, our tools and technologies appear to fix materials in place. Disassembly is one practice that provides openings to explore and understand the dynamic nature of material. In this research, we investigate possibilities that emerge from disassembly. Specifically, we studied how novices disassembled a common digital artifact-desktop printers. We worked with 21 young people and family members across two evening workshops at a middle school. We report on the workshop interactions, categories of actions of disassembly, and four in-depth vignettes showcasing disassembly in action. In the discussion, we reflect on disassembly and permission, sustainability, the joy of disassembling, and design considerations in support of disassembly. Our contributions include: (1) extending existing theoretical framings about artifacts and materials; (2) an empirical study documenting the process by which novices disassemble; and (3) preliminary design and policy considerations that enable disassembly.

"Human, All Too Human": NOAA Weather Radio and the Emotional Impact of Synthetic Voices

The integration of text-to-speech into an open technology stack for low-power FM community radio stations is an opportunity to automate laborious processes and increase accessibility to information in remote communities. However, there are open questions as to the perceived contrast of synthetic voices with the local and intimate format of community radio. This paper presents an exploratory focus group on the topic, followed by a thematic analysis of public comments on YouTube videos of the synthetic voices used for broadcasting by National Oceanic and Atmospheric Administration (NOAA) Weather Radio. We find that despite observed reservations about the suitability of TTS for radio, there is significant evidence of anthropomorphism, nostalgia and emotional connection in relation to these voices. Additionally, introduction of a more "human sounding" synthetic voice elicited significant negative feedback. We identify pronunciation, speed, suitability to content and acknowledgment of limitations as more relevant factors in listeners' stated sense of connection.

Privacy and Activism in the Transgender Community

Transgender people are marginalized, facing specific privacy concerns and high risk of online and offline harassment, discrimination, and violence. They also benefit tremendously from technology. We conducted semi-structured interviews with 18 transgender people from 3 U.S. cities about their computer security and privacy experiences broadly construed. Participants frequently returned to themes of activism and prosocial behavior, such as protest organization, political speech, and role-modeling transgender identities, so we focus our analysis on these themes. We identify several prominent risk models related to visibility, luck, and identity that participants used to analyze their own risk profiles, often as distinct or extreme. These risk perceptions may heavily influence transgender people's defensive behaviors and self-efficacy, jeopardizing their ability to defend themselves or gain technology's benefits. We articulate design lessons emerging from these ideas, contrasting and relating them to lessons about other marginalized groups whenever possible.

Improving Humans' Ability to Interpret Deictic Gestures in Virtual Reality

Collaborative Virtual Environments (CVEs) offer unique opportunities for human communication. Humans can interact with each other over a distance in any environment and visual embodiment they want. Although deictic gestures are especially important as they can guide other humans' attention, humans make systematic errors when using and interpreting them. Recent work suggests that the interpretation of vertical deictic gestures can be significantly improved by warping the pointing arm. In this paper, we extend previous work by showing that models enable to also improve the interpretation of deictic gestures at targets all around the user. Through a study with 28 participants in a CVE, we analyzed the errors users make when interpreting deictic gestures. We derived a model that rotates the arm of a pointing user's avatar to improve the observing users' accuracy. A second study with 24 participants shows that we can improve observers' accuracy by 22.9%. As our approach is not noticeable for users, it improves their accuracy without requiring them to learn a new interaction technique or distracting from the experience.

Understanding Client Support Strategies to Improve Clinical Outcomes in an Online Mental Health Intervention

Online mental health interventions are increasingly important in providing access to, and supporting the effectiveness of, mental health treatment. While these technologies are effective, user attrition and early disengagement are key challenges. Evidence suggests that integrating a human supporter into such services mitigates these challenges, however, it remains under-studied how supporter involvement benefits client outcomes, and how to maximize such effects. We present our analysis of 234,735 supporter messages to discover how different support strategies correlate with clinical outcomes. We describe our machine learning methods for: (i) clustering supporters based on client outcomes; (ii) extracting and analyzing linguistic features from supporter messages; and (iii) identifying context-specific patterns of support. Our findings indicate that concrete, positive and supportive feedback from supporters that reference social behaviors are strongly associated with better outcomes; and show how their importance varies dependent on different client situations. We discuss design implications for personalized support and supporter interfaces.

IoT Data in the Home: Observing Entanglements and Drawing New Encounters

Internet of Things (IoT) technologies for the home are gaining in popularity, generating exponential data byproducts. Yet, everyday relationships between home dwellers and domestic IoT data often remain secondary interactions, preventing deeper understanding and awareness of data tracked in the home. Our paper offers a design ethnography and design inquiry which examine these human-data entanglements. Findings from working with 10 inhabitants who interact with their IoT data illustrate five characteristics of current data encounters: manifesting, inquiring, exposing, repositioning, and broadening. In response, we used speculative sketches to refine, refract and complicate these encounters. We argue that data do not have to be laborious, tidy or the byproduct of a service, but rather lively and affecting. We further suggest new modes of engagement with data which expand or step away from self-improvement and reflection: through diverse acts of noticing, by allowing data to remain invisible, and by embracing imaginative practices.

Interactive Multisensory Environments for Primary School Children

Interactive Multi-Sensory Environments (iMSEs) are room-sized interactive installations equipped with digitally enriched physical materials and ambient embedded devices. These items can sense users' presence, gestures, movements, and manipulation, and react by providing gentle stimulation (e.g., light, sound, projections, blowing bubbles, tactile feel, aromas) to different senses. Most of prior research on iMSEs investigates their use for persons with disabilities (e.g., autism). Our work focuses on the use of iMSEs in primary education contexts and for mixed groups of young students, i.e., children with and without disability. The paper describes the latest version of an iMSE called Magic Room that has been installed in two local schools. We report two empirical studies devoted to understand how the Magic Room could be used in inclusive educational settings, and to explore its potential benefits.

Parenting with Alexa: Exploring the Introduction of Smart Speakers on Family Dynamics

Smart speakers have become pervasive in family homes, creating the potential for these devices to influence parent-child dynamics and parenting behaviors. We investigate the impact of introducing a smart speaker to 10 families with children, over four weeks. We use pre- and post- deployment interviews with the whole family and in-home audio capture of parent-child interactions with the smart speaker for our analysis. Despite the smart speaker causing occasional conflict in the home, we observed that parents lever-aged the smart speaker to further parenting goals. We found three forms of influence the smart speaker has on family dynamics: 1) fostering communication, 2) disrupting access, and 3) augmenting parenting. All of these influences arise from a communally accessible, stand-alone voice interface which democratizes family access to technology. We discuss design implications in furthering parenting practices and behaviors as the capabilities of the technology continue to improve.

Making Design Memoirs: Understanding and Honoring Difficult Experiences

Design is commonly understood as a storytelling practice, yet we have few narratives with which to describe the felt experiences of struggle, pain, and difficulty, beyond treating them as subjects to resolve. This work uses the praxis of embodied design as a way to bring more complex narratives to the community for contemplation---to engage and entangle personal and difficult stories within a public context. We propose the term Design Memoirs for these first-person practices and reflections. Design Memoirs are subjective and corporeal in nature, and provide a direct and observable way to reckon with felt experiences through, and for, design. We demonstrate Design Memoirs by drawing on our own experiences as mothers, caregivers, and corporeal subjects. Following Barad, we propose a practice of diffractive reading to locate resonances between Design Memoirs which render difficult autobiographical material addressable, shareable, and open for new interpretations. We present this strategy as a method for arriving at deeper understandings of difficult experiences.

The Influence of Decaying the Representation of Older Social Media Content on Simulated Hiring Decisions

Decaying representations gradually make social media content less visible to readers over time, which can help users disassociate from past online activities. We explore whether shrinking, one decaying representation, influences managers' assessments and simulated hiring decisions of job candidates, compared to seeing a full profile or an empty profile with no posts. Our 3 x 2 between-subjects crowdsourced survey (N = 360 US managers) shows that shrunk or empty profiles led to more positive decisions than profiles in their original full format. However, shrunk profiles also further contributed to more positive impressions of the candidates. Shrinking did not help the candidate of either gender more than the other and demographics of managers had limited impact on their assessment. Further, our managers regularly search job candidates' social media profiles in real life, suggesting that shrinking could support users' privacy. We finally present implications for individuals' privacy on social media.

Sensor Illumination: Exploring Design Qualities and Ethical Implications of Smart Cameras and Image/Video Analytics

Drawing analogies between smart cameras and electric lighting, we highlight and extrapolate design trends towards always-on sensing in intimate contexts, and the functional expansion of smart cameras as general-purpose and multi-functional devices. Employing a research through design (RtD) approach, we extrapolate these trends using speculative scenarios, materialize the scenarios by designing and constructing lighting-inspired smart camera fixtures, and self-experiment with these fixtures to introduce and exacerbate privacy and security issues, and inspire creative workarounds and design opportunities for sensor-level regulation. We synthesize our insights by presenting 8 smart camera sensing design qualities for addressing privacy, security, and related social and ethical issues.

Dear Pictograph: Investigating the Role of Personalization and Immersion for Consuming and Enjoying Visualizations

Much of the visualization literature focuses on assessment of visual representations with regard to their effectiveness for understanding data. In the present work, we instead focus on making data visualization experiences more enjoyable, to foster deeper engagement with data. We investigate two strategies to make visualization experiences more enjoyable and engaging: personalization, and immersion. We selected pictographs (composed of multiple data glyphs) as this representation affords creative freedom, allowing people to craft symbolic or whimsical shapes of personal significance to represent data. We present the results of a qualitative study with 12 participants crafting pictographs using a large pen-enabled device and while immersed within a VR environment. Our results indicate that personalization and immersion both have positive impact on making visualizations more enjoyable experiences.

Explore, Create, Annotate: Designing Digital Drawing Tools with Visually Impaired People

People often use text in their drawings to communicate their ideas. For visually impaired people, adding textual information to tactile graphics is challenging. Labeling in braille is a laborious process and clutters the drawings. Audio labels provide an alternative way to add text. However, digital drawing tools for visually impaired people have not examined the use of audio for creating labels. We conducted a study comprising three tasks with 11 visually impaired adults. Our goal was to understand how participants explored and created labeled tactile graphics (both braille and audio), and their interaction preferences. We find that audio labels were quicker to use and easier to create. However, braille labels enabled flexible exploration strategies. We also find that participants preferred multimodal interaction commands, and report hand postures and movements observed during the drawing process for designing recognizable interactions. Based on our findings, we derive design implications for digital drawing tools.

A Comparison of Geographical Propagation Visualizations

Geographical propagation phenomena occur in multiple domains, such as in epidemiology and social media. Propagation dynamics are often complex, and visualizations play a key role in helping subject-matter experts understand and analyze them. However, there is little empirical data about the effectiveness of the various strategies used to visualize geographical propagation. To fill this gap, we conduct an experiment to evaluate the effectiveness of three strategies: an animated map, small-multiple maps, and a single map with glyphs. We compare them under five tasks that vary in one of the following dimensions: propagation scope, direction, speed, peaks, and spatial jumps. Our results show that small-multiple maps perform best overall, but that the effectiveness of each visualization varies depending on the task considered.

Understanding Women Modders using the Serious Leisure Perspective

Modding, the act of custom creation in videogames, is a large enterprise comprising millions of people. Despite the large number of individuals creating mods, our understanding of who modders are and their motivation for modding is limited. This is especially true for minority groups, including women. In prior research with modding communities, women modders were consistently underrepresented. Using a mixed-method survey (N = 68) that incorporates the Serious Leisure Framework, this study begins to unravel women's participation in modding activities. We begin to identify who women modders are, examine what motivates them to mod, and investigate their modding practices. Results show that women modders value the creation of multiple mod types, including cosmetic, environmental and gameplay modification. They are primarily motivated by self-gratification and enjoyment. These findings create new insights into how women interact with gaming environments, as well as identifying those aspects of the experience that motivate women's engagement in modding.

I am Not an Object: Reframing 3D Body Scanning for Co-Design

3D scanning technologies provide designers with tools to generate a digital representation of the human body that can be used in the design of ultra-personalized apparel and wearables. However, prior work shows that the body scanning process can be an uncomfortable experience for users. In this work, we take a first-person perspective to identify frictions in the experience of being body scanned compared to having one's body measurements taken by a professional tailor. Based on our findings, we offer a reframing of body scanning as a collaborative process, and discuss implications for the design of tools and processes that shift agency in the generation of body data towards users. Our paper is relevant to design researchers and practitioners interested in taking a co-design approach to ultra-personalization.

Virtual Reality Without Vision: A Haptic and Auditory White Cane to Navigate Complex Virtual Worlds

Current Virtual Reality (VR) technologies focus on rendering visuospatial effects, and thus are inaccessible for blind or low vision users. We examine the use of a novel white cane controller that enables navigation without vision of large virtual environments with complex architecture, such as winding paths and occluding walls and doors. The cane controller employs a lightweight three-axis brake mechanism to provide large-scale shape of virtual objects. The multiple degrees-of-freedom enables users to adapt the controller to their preferred techniques and grip. In addition, surface textures are rendered with a voice coil actuator based on contact vibrations; and spatialized audio is determined based on the progression of sound through the geometry around the user. We design a scavenger hunt game that demonstrates how our device enables blind users to navigate a complex virtual environment. Seven out of eight users were able to successfully navigate the virtual room (6x6m) to locate targets while avoiding collisions. We conclude with design consideration on creating immersive non-visual VR experiences based on user preferences for cane techniques, and cane material properties.

Clash of Times: Respectful Technology Space for Integrating Community Stories in Intangible Exhibits

Emerging research in Human Computer Interaction (HCI) has considered the use of technology to preserve Intangible Cultural Heritage (ICH) while wrestling with the dilemma of local participation in the face of post-colonialism. There remains a need to understand how ICH is portrayed by museums and texts, how communities regard these representations, and how technology would affect preservation. We conducted a study in the North Rift region of Kenya to understand how ICH is preserved and disseminated by the museum in comparison with the community. The findings describe a respectful technology space where community needs and museum needs can co-exist. We also articulate social challenges that should be considered by designers when recommending or designing technological solutions. This paper concludes by recommending ways for researchers to smoothly integrate technology with ICH through community participation and an awareness of the respectful space.

Transforming Robot Programs Based on Social Context

Social robots have varied effectiveness when interacting with humans in different interaction contexts. A robot programmed to escort individuals to a different location, for instance, may behave more appropriately in a crowded airport than a quiet library, or vice versa. To address these issues, we exploit ideas from program synthesis and propose an approach to transforming the structure of hand-crafted interaction programs that uses user-scored execution traces as input, in which end users score their paths through the interaction based on their experience. Additionally, our approach guarantees that transformations to a program will not violate task and social expectations that must be maintained across contexts. We evaluated our approach by adapting a robot program to both real-world and simulated contexts and found evidence that making informed edits to the robot's program improves user experience.

Digital Technology, Meditative and Contemplative Practices, and Transcendent Experiences

Meditative and contemplative practices are common among U.S. adults, but the impact of digital technology use on these practices and on associated transcendent experiences is poorly understood. Through semi-structured interviews with sixteen experienced practitioners from a variety of traditions, we find that practitioners consider digital technology to be a mixed blessing. While they see its practical value, they are wary of its stimulation-based effects and find minimal usefulness in commercial meditation apps. They also feel that digital technology use may interfere with possible transcendent experiences. The practitioners, however, applied insights from their respective practices to strategically mitigate digital technology's negative effects in three ways: limiting its use to instrumental purposes, using technology interactions as grist for self-reflection, and integrating technology itself into a site for practice. Specific design recommendations are discussed.

The Silent Conversation: Designing for Introspection and Social Play in Art Museums

This paper presents an attempt to design for a combination of social play and introspection using a ludic approach within an art museum setting. The field trial is described of a mobile web app called 'Never let me go', a two-player system enabling visitors to an art museum to create impromptu experiences in-situ for a companion. The study reveals that players used the app for communicating with each other during the visit, often without speaking. This led to deeply personal and introspective moments, as well as, lots of teasing and playing. The implications of allowing for social, personal and playful experiences in an art museum are discussed, as well as, the advantages and challenges of designing for improvisation.

PoCoPo: Handheld Pin-based Shape Display for Haptic Rendering in Virtual Reality

We introduce PoCoPo, the first handheld pin-based shape display that can render various 2.5D shapes in hand in realtime. We designed the display small enough for a user to hold it in hand and carry it around, thereby enhancing the haptic experiences in a virtual environment. PoCoPo has 18 motor-driven pins on both sides of a cuboid, providing the sensation of skin contact on the user's palm and fingers. We conducted two user studies to understand the capability of PoCoPo. The first study showed that the participants were generally successful in distinguishing the shapes rendered by PoCoPo with an average success rate of 88.5%. In the second study, we investigated the acceptable visual size of a virtual object when PoCoPo rendered a physical object of a certain size. The result led to a better understanding of the acceptable differences between the perceptions of visual size and haptic size.

Understanding Parenting Stress through Co-designed Self-Trackers

New parents often experience significant stress as they take on new roles and responsibilities. Stress management and mental wellbeing are two areas in which personal informatics (PI) research has gained attention, and there is an opportunity to investigate how parenting stress can be mitigated through PI practices. In this paper, we present the results of a co-designed technology probe study through which we deployed individualized self-trackers with new parents. We investigate the stress management topics new parents are interested in tracking and how — and with what goals---they engage in self-directed PI practices. Our findings indicate that PI practices can potentially enable parents to: re-discover positive aspects of their everyday lives; identify better-suited stress management strategies; and facilitate spousal communication about shared responsibilities. We discuss how self-tracking experiences for the mental wellness of parents can be better designed.

Investigating User-Created Gamification in an Image Tagging Task

Commonly, gamification is designed by developers and not by end-users. In this paper we investigate an approach where users take control of this process. Firstly, users were asked to describe their own gamification concepts which would motivate them to put more effort into an image tagging task. We selected this task as gamification has already been shown to be effective here in previous work. Based on these descriptions, an implementation was made for each concept and given to the creator. In a between-subjects study (n=71), our approach was compared to a no-gamification condition and two conditions with fixed gamification settings. We found that providing participants with an implementation of their own concept significantly increased the amount of generated tags compared to the other conditions. Although the quality of tags was lower, the number of usable tags remained significantly higher in comparison, suggesting the usefulness of this approach.

Supporting Stimulation Needs in Dementia Care through Wall-Sized Displays

Beside reminiscing, the increasing cognitive decline in dementia can also be addressed through sensory stimulation allowing the immediate, nonverbal engagement with the world through one's senses. Much HCI work has prioritized cognitive stimulation for reminiscing or personhood often on small screens, while less research has explored sensory stimulation like the one enabled by large displays. We describe a year-long deployment in a residential care home of a wall-sized display, and explored its domestication through 24 contextual interviews. Findings indicate strong engagement and attachment to the display which has inspired four psychosocial interventions using online generic content. We discuss the value of these findings for personhood through residents' exercise of choices, the tension between generic/personal content and its public/private use, the importance of participatory research approach to domestication, and the infrastructure-based prototype, illustrated by the DementiaWall and its generative quality.

Designing Mental Health Technologies that Support the Social Ecosystem of College Students

The last decade has seen increased reports of mental health problems among college students, with college counseling centers struggling to keep up with the demand for services. Digital mental health tools offer a potential solution to expand the reach of mental health services for college students. In this paper, we present findings from a series of design activities conducted with college students and counseling center staff aimed at identifying needs and preferences for digital mental health tools. Results emphasize the social ecosystems and social support networks in a college student's life. Our findings highlight the predominant role of known peers, and the ancillary roles of unknown peers and non-peers (e.g., faculty, family) in influencing the types of digital mental health tools students desire, and the ways in which they want to learn about mental health tools. We identify considerations for designing digital mental health tools for college students that take into account the identified social factors and roles.

Community Collectives: Low-tech Social Support for Digitally-Engaged Entrepreneurship

With the rise of social media, entrepreneurs are feeling the pressure to adopt digital tools for their work. However, the upfront effort and resources needed to participate on these platforms is ever more complex, particularly in underresourced contexts. Through participatory action research over two years in Detroit's Eastside, we found that local entrepreneurs preferred to become engaged digitally through a community collective, which involved (a) resource-connecting organizations, (b) regular in-person meetings, (c) paper planning tools, and (d) practice and validation. Together, these elements combined to provide (1) awareness and willingness to use digital tools, (2) regular opportunities to build internet self-efficacy, and (3) ways to collectively overcome digital obstacles. We discuss our findings in the context of digital engagement and entrepreneurship, and outline recommendations for digital platforms seeking to better support economic mobility more broadly.

Designing Distributed Ledger Technologies for Social Change: The Case of CariCrop

Distributed ledger technologies (DLTs) have been celebrated for promoting transparency, trust, and efficiency in several domains. However, recent research has also pointed out the potential of these technologies to increase power asymmetries and deepen social inequality. In this paper, we contribute to this discussion by reporting on a collective effort of academics, development partners, local authorities, businesses, and farming groups to look at the potential of DLTs, particularly Blockchains, to support socio-economic development in rural communities in the Caribbean. We present a series of design concepts resulting from this effort and reflect on a method to facilitate stakeholders' experience of possible implementations and enable them to voice concerns, preferences, and expectations. Results from workshops with different groups of stakeholders contribute insights into opportunities and limitations of these applications to enable social development and to level the playing field in agricultural exchanges in developing countries.

Du Bois Wrapped Bar Chart: Visualizing Categorical Data with Disproportionate Values

We propose a visualization technique, Du Bois wrapped bar chart, inspired by work of W.E.B Du Bois. Du Bois wrapped bar charts enable better large-to-small bar comparison by wrapping large bars over a certain threshold. We first present two crowdsourcing experiments comparing wrapped and standard bar charts to evaluate (1) the benefit of wrapped bars in helping participants identify and compare values; (2) the characteristics of data most suitable for wrapped bars. In the first study (n=98) using real-world datasets, we find that wrapped bar charts lead to higher accuracy in identifying and estimating ratios between bars. In a follow-up study (n=190) with 13 simulated datasets, we find participants were consistently more accurate with wrapped bar charts when certain category values are disproportionate as measured by entropy and H-spread. Finally, in an in-lab study, we investigate participants' experience and strategies, leading to guidelines for when and how to use wrapped bar charts.

PhysioSkin: Rapid Fabrication of Skin-Conformal Physiological Interfaces

Advances in rapid prototyping platforms have made physiological sensing accessible to a wide audience. However, off-the-shelf electrodes commonly used for capturing biosignals are typically thick, non-conformal and do not support customization. We present PhysioSkin, a rapid, do-it-yourself prototyping method for fabricating custom multi-modal physiological sensors, using commercial materials and a commodity desktop inkjet printer. It realizes ultrathin skin-conformal patches (~1μm) and interactive textiles that capture sEMG, EDA and ECG signals. It further supports fabricating devices with custom levels of thickness and stretchability. We present detailed fabrication explorations on multiple substrate materials, functional inks and skin adhesive materials. Informed from the literature, we also provide design recommendations for each of the modalities. Evaluation results show that the sensor patches achieve a high signal-to-noise ratio. Example applications demonstrate the functionality and versatility of our approach for prototyping a next generation of physiological devices that intimately couple with the human body.

Tactile Presentation of Network Data: Text, Matrix or Diagram?

Visualisations are commonly used to understand social, biological and other kinds of networks. Currently we do not know how to effectively present network data to people who are blind or have low-vision (BLV). We ran a controlled study with 8 BLV participants comparing four tactile representations: organic node-link diagram, grid node-link diagram, adjacency matrix and braille list. We found that the node-link representations were preferred and more effective for path following and cluster identification while the matrix and list were better for adjacency tasks. This is broadly in line with findings for the corresponding visual representations.

PV-Tiles: Towards Closely-Coupled Photovoltaic and Digital Materials for Useful, Beautiful and Sustainable Interactive Surfaces

The interactive, digital future with its seductive vision of Internet-of-Things connected sensors, actuators and displays comes at a high cost in terms of both energy demands and the clutter it brings to the physical world. But what if such devices were made of materials that enabled them to self-power their interactive features? And, what if those materials were directly used to build aesthetically pleasing environments and objects that met practical physical needs as well as digital ones? In this paper we introduce PV-Tiles ? a novel material that closely couples photovoltaic energy harvesting and light sensing materials with digital interface components. We consider potential contexts, use-cases and light gestures surfaced through co-creation workshops; and, present initial technological designs and prototypes. The work opens a new set of opportunities and collaborations between HCI and material science, stimulating technical and design pointers to accommodate and exploit the material's properties.

Celebrating Everyday Success: Improving Engagement and Motivation using a System for Recording Daily Highlights

The demands of daily work offer few opportunities for workers to take stock of their own progress, big or small, which can lead to lower motivation, engagement, and higher risk of burnout. We present Highlight Matome, a personal online tool that encourages workers to quickly record and rank a single work highlight each day, helping them gain awareness of their own successes. We describe results from a field experiment investigating our tool's effectiveness for improving workers' engagement, perceptions, and affect. Thirty-three knowledge workers in Japan and the U.S. used Highlight Matome for six weeks. Our results show that using our tool for less than one minute each day significantly increased measures of work engagement, dedication, and positivity. A qualitative analysis of the highlights offers a window into participants' emotions and perceptions. We discuss implications for theories of inner work life and worker well-being.

Shaping the Design of Smartphone-Based Interventions for Self-Harm

Self-harm is a prevalent issue amongst young people, yet it is thought around 40% will never seek professional help due to stigma surrounding it. It is generally a way of coping with emotional distress and can have a range of triggers which are highly heterogeneous to the individual. In a move towards enhancing the accessibility of personalized interventions for self-harm, we undertook a three-stage study. We first conducted interviews with 4 counsellors in self-harm to understand how they clinically respond to self-harm triggers. We then ran a survey with 37 young people, to explore perceptions of mobile sensing, and current and future uses for smartphone-based interventions. Finally, we ran a workshop with 11 young people to further explore how a context-aware self-management application might be used to support them. We contribute an in-depth understanding of how triggers for self-harm might be identified and subsequently predicted and prevented using mobile-sensing technology.

Embedding a VR Game Studio in a Sedentary Workplace: Use, Experience and Exercise Benefits

Many people, especially those in sedentary occupations, fail to achieve the recommended levels of physical activity. Virtual reality (VR) games have the potential to overcome this because they are fun and also can be physically demanding. This paper explores whether a VR game studio can help workers in sedentary jobs to get valuable levels of exercise. We studied how 11 participants used our VR game studio in a sedentary workplace over 8-weeks and their perceptions of the experience. We analysed the physical exertion in the VR game studio, comparing this to their step counts from a smartwatch. All participants achieved valuable levels of physical activity and mood benefits. Importantly, for 6 participants, only with the VR game studio did they meet recommended activity levels. Our key contributions are insights about the use of a workplace VR game studio and its health benefits.

Embodiment Effects in Interactions with Failing Robots

The increasing use of robots in real-world applications will inevitably cause users to encounter more failures in interactions. While there is a longstanding effort in bringing human-likeness to robots, how robot embodiment affects users' perception of failures remains largely unexplored. In this paper, we extend prior work on robot failures by assessing the impact that embodiment and failure severity have on people's behaviours and their perception of robots. Our findings show that when using a smart-speaker embodiment, failures negatively affect users' intention to frequently interact with the device, however not when using a human-like robot embodiment. Additionally, users significantly rate the human-like robot higher in terms of perceived intelligence and social presence. Our results further suggest that in higher severity situations, human-likeness is distracting and detrimental to the interaction. Drawing on quantitative findings, we discuss benefits and drawbacks of embodiment in robot failures that occur in guided tasks.

PuffPacket: A Platform for Unobtrusively Tracking the Fine-grained Consumption Patterns of E-cigarette Users

The proliferation of e-cigarettes and portable vaporizers presents new opportunities for accurately and unobtrusively tracking e-cigarette use. PuffPacket is a hardware and soft-ware research platform that leverages the technology built into vaporizers, e-cigarettes and other electronic drug delivery devices to ubiquitously track their usage. The system piggybacks on the signals these devices use to directly measure and track the nicotine consumed by users. PuffPacket augments e-cigarettes with Bluetooth to calculate the frequency, intensity, and duration of each inhalation. This information is augmented with smartphone-based location and activity information to help identify potential contextual triggers. Puff-Packet is generalizable to a wide variety of electronic nicotine,THC, and other drug delivery devices currently on the mar-ket. The hardware and software for PuffPacket is open-source so it can be expanded upon and leveraged for mobile health tracking research.

WeDA: Designing and Evaluating A Scale-driven Wearable Diagnostic Assessment System for Children with ADHD

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common mental disorders affecting children. Because the etiology of ADHD is complex and its symptoms are not specific, there is a lack of feasible quantitative diagnostic methods. Pursuing objective and non-invasive detection methods and standards is of great practical significance to prevent the development of the disease. In this study, we aim to address one specific concern about the objectivity and quantification of ADHD diagnosis. Over a year, we iteratively designed and tested WeDA, a scale-driven wearable diagnostic assessment system. This system contains an Android computer machine with a large touchscreen, a suite of 3D printed interactive devices, and six wearable motion sensors. We implement ten diagnostic tasks drawing on the symptoms of ADHD based on DSM-5. The experimental results of classifying children with ADHD and typically developing children and subjective evaluations from doctors, parents, and children validate the effectiveness and acceptability of WeDA.

Crowdsourced Detection of Emotionally Manipulative Language

Detecting rhetoric that manipulates readers' emotions requires distinguishing intrinsically emotional content (IEC; e.g., a parent losing a child) from emotionally manipulative language (EML; e.g., using fear-inducing language to spread anti-vaccine propaganda). However, this remains an open classification challenge for both automatic and crowdsourcing approaches. Machine Learning approaches only work in narrow domains where labeled training data is available, and non-expert annotators tend to conflate IEC with EML. We introduce an approach, anchor comparison, that leverages workers' ability to identify and remove instances of EML in text to create a paraphrased "anchor text", which is then used as a comparison point to classify EML in the original content. We evaluate our approach with a dataset of news-style text snippets and show that precision and recall can be tuned for system builders' needs. Our contribution is a crowdsourcing approach that enables non-expert disentanglement of social references from content.

Conversational Agency in Augmentative and Alternative Communication

Augmented communicators (ACs) use augmentative and alternative communication (AAC) technologies to speak. Prior work in AAC research has looked to improve efficiency and expressivity of AAC via device improvements and user training. However, ACs also face constraints in communication beyond their device and individual abilities such as when they can speak, what they can say, and who they can address. In this work, we recast and broaden this prior work using conversational agency as a new frame to study AC communication. We investigate AC conversational agency with a study examining different conversational tasks between four triads of expert ACs, their close conversation partners (paid aide or parent), and a third party (experimenter). We define metrics to analyze AAC conversational agency quantitatively and qualitatively. We conclude with implications for future research to enable ACs to easily exercise conversational agency.

Prior Setting in Practice: Strategies and Rationales Used in Choosing Prior Distributions for Bayesian Analysis

Bayesian statistical analysis is steadily growing in popularity and use. Choosing priors is an integral part of Bayesian inference. While there exist extensive normative recommendations for prior setting, little is known about how priors are chosen in practice. We conducted a survey (N = 50) and interviews (N = 9) where we used interactive visualizations to elicit prior distributions from researchers experienced withBayesian statistics and asked them for rationales for those priors. We found that participants' experience and philosophy influence how much and what information they are willing to incorporate into their priors, manifesting as different levels of informativeness and skepticism. We also identified three broad strategies participants use to set their priors: centrality matching, interval matching, and visual mass allocation. We discovered that participants' understanding of the notion of 'weakly informative priors"-a commonly-recommended normative approach to prior setting-manifests very differently across participants. Our results have implications both for how to develop prior setting recommendations and how to design tools to elicit priors in Bayesian analysis.

Pac-Euglena: A Living Cellular Pac-Man Meets Virtual Ghosts

The advancement of biotechnology enabled the development of "biotic video games", where human players manipulate real biological samples for fun and educational human-biology interactions. However, new design principles are needed to both leverage and mitigate biological properties (e.g., variability and stochasticity), and create unique play experiences that transcend traditional video games. This paper describes the implementation of Pac-Euglena, a biotic Pac-Man analog, where players guide live microscopic Euglena cells with light stimuli through a physical microfluidic maze. Through use of multi-modal stimuli, a mixed biology-digital-human reality is achieved, enabling cell interactions with virtual ghosts and collectibles. Through an iterative design process, we illustrate challenges and strategies for designing games with living organisms. A user study (n=18, conducted at a university event) showed that Pac-Euglena was fun, stimulated curiosity, and taught users about Euglena. We conclude with five general guidelines for the design and development of biotic games and HBI interfaces.

Proxemics Beyond Proximity: Designing for Flexible Social Interaction Through Cross-Device Interaction

Cross-device interactions enable ad hoc sharing of content and control in co-located collaboration. Cross-device research often draws from proxemics theory for designing interactions based on detection of spatial relations such as distance and orientation between people and devices. However, detection of human-human or human-device proximity also constrains flexibility in co-located social interaction. We suggest a proxemics-based approach to designing flexible cross-device interactions. From observations in a field study, we articulate how co-located sharing practices are shaped by the interplay between everyday mobile devices and the physical environment. Based on these insights, we present three cross-device prototypes as proofs-of-concept, demonstrating three design sensitivities for considering proxemics beyond proximity; incorporating features in the environment, enabling flexibility in interpersonal distance and orientation, and providing multiple alternative action possibilities. Drawing from characteristics of our prototypes, we discuss concrete proposals for designing cross-device interactions to enable flexible social interaction.

Decipher: An Interactive Visualization Tool for Interpreting Unstructured Design Feedback from Multiple Providers

Feedback from diverse audiences can vary in focus, differ in structure, and contradict each other, making it hard to interpret and act on. While prior work has explored generating quality feedback, our work helps a designer interpret that feedback. Through a formative study with professional designers (N=10), we discovered that the interpretation process includes categorizing feedback, identifying valuable feedback, and prioritizing which feedback to incorporate in a revision. We also found that designers leverage feedback topic and sentiment, and the status of the provider to aid interpretation. Based on the findings, we created a new tool (Decipher) that enables designers to visualize and navigate a collection of feedback using its topic and sentiment structure. In a preliminary evaluation (N=20), we found that Decipher helped users feel less overwhelmed during feedback interpretation tasks and better attend to critical issues and conflicting opinions compared to using a typical document-editing tool.

Evaluating Multivariate Network Visualization Techniques Using a Validated Design and Crowdsourcing Approach

Visualizing multivariate networks is challenging because of the trade-offs necessary for effectively encoding network topology and encoding the attributes associated with nodes and edges. A large number of multivariate network visualization techniques exist, yet there is little empirical guidance on their respective strengths and weaknesses. In this paper, we describe a crowdsourced experiment, comparing node-link diagrams with on-node encoding and adjacency matrices with juxtaposed tables. We find that node-link diagrams are best suited for tasks that require close integration between the network topology and a few attributes. Adjacency matrices perform well for tasks related to clusters and when many attributes need to be considered. We also reflect on our method of using validated designs for empirically evaluating complex, interactive visualizations in a crowdsourced setting. We highlight the importance of training, compensation, and provenance tracking.

Enabling Data-Driven API Design with Community Usage Data: A Need-Finding Study

APIs are becoming the fundamental building block of modern software and their usability is crucial to programming efficiency and software quality. Yet API designers find it hard to gather and interpret user feedback on their APIs. To close the gap, we interviewed 23 API designers from 6 companies and 11 open-source projects to understand their practices and needs. The primary way of gathering user feedback is through bug reports and peer reviews, as formal usability testing is prohibitively expensive to conduct in practice. Participants expressed a strong desire to gather real-world use cases and understand users' mental models, but there was a lack of tool support for such needs. In particular, participants were curious about where users got stuck, their workarounds, common mistakes, and unanticipated corner cases. We highlight several opportunities to address those unmet needs, including developing new mechanisms that systematically elicit users' mental models, building mining frameworks that identify recurring patterns beyond shallow statistics about API usage, and exploring alternative design choices made in similar libraries.

Synthesized Social Signals: Computationally-Derived Social Signals from Account Histories

Social signals are crucial when we decide if we want to interact with someone online. However, social signals are typically limited to the few that platform designers provide, and most can be easily manipulated. In this paper, we propose a new idea called synthesized social signals (S3s): social signals computationally derived from an account's history, and then rendered into the profile. Unlike conventional social signals such as profile bios, S3s use computational summarization to reduce receiver costs and raise the cost of faking signals. To demonstrate and explore the concept, we built Sig, an extensible Chrome extension that computes and visualizes S3s. After a formative study, we conducted a field deployment of Sig on Twitter, targeting two well-known problems on social media: toxic accounts and misinformation. Results show that Sig reduced receiver costs, added important signals beyond conventionally available ones, and that a few users felt safer using Twitter as a result. We conclude by reflecting on the opportunities and challenges S3s provide for augmenting interaction on social platforms.

Evaluating the Information Security Awareness of Smartphone Users

Information security awareness (ISA) is a practice focused on the set of skills which help a user successfully mitigate social engineering (SE) attacks. Evaluating the ISA of users is crucial, since early identification of users who are more vulnerable to SE attacks improves system security. Previous studies for evaluating the ISA of smartphone users rely on subjective data sources (questionnaires) and do not address the differences between classes of SE attacks. This paper presents a framework for evaluating the ISA of smartphone users for specific attack classes. In addition to questionnaires, we utilize objective data sources: a mobile agent, a network traffic monitor, and cybersecurity challenges. We evaluated the framework by conducting a long-term user study involving 162 users. The results show that: the self-reported behavior of users differs significantly from their actual behavior and the ISA level derived from the actual behavior of users is highly correlated with their ability to mitigate SE attacks.

Choice-Point: Fostering Awareness and Choice with Perpetrators in Domestic Violence Interventions

Learning about alternatives to violence is an essential part of change work with domestic violence perpetrators. This is complex work, seeking to tackle a sensitive issue by involving the development of deep, embodied learning for perpetrators who may lack perspective on their behaviour. Interactive storytelling has been providing users with the opportunity to explore speculative scenarios in a controlled environment. We discuss the design of Choice-Point: a web-based application that allows perpetrators adopt the role of different fictional characters in an abusive scenario for conveying the essential skill of perspective-taking. We evaluated Choice-Point through trials with three groups of perpetrators, a support group of victim-survivors and an expert critique from support workers. We discuss challenges in using such technologies - such as our system - for engagement; the value of perpetrator agency in supporting non-violent behaviours, and the potential to positively shape perpetrators' journeys to non-violence within social care settings.

Sensock: 3D Foot Reconstruction with Flexible Sensors

Capturing 3D foot models is important for applications such as manufacturing customized shoes and creating clubfoot orthotics. In this paper, we propose a novel prototype, Sensock, to offer a fully wearable solution for the task of 3D foot reconstruction. The prototype consists of four soft stretchable sensors, made from silk fibroin yarn. We identify four characteristic foot girths based on the existing knowledge of foot anatomy, and measure their lengths with the resistance value of the stretchable sensors. A learning-based model is trained offline and maps the foot girths to the corresponding 3D foot shapes. We compare our method with existing solutions using red-green-blue (RGB) or RGBD (RGB-depth) cameras, and show the advantages of our method in terms of both efficiency and accuracy. In the user experiment, we find that the relative error of Sensock is lower than 0.55%. It performs consistently across different trials and is considered comfortable and suitable for long-term wearing.

Tabloidization versus Credibility: Short Term Gain for Long Term Pain

Print news agencies have been under pressure from falling sales and advertising revenue and increased competition. As the Internet became the dominant medium, news agencies invested heavily in their websites and apps, providing their news for free, rather than selling a print edition. Reducing the cost of production and removing access barriers such as geographic location had the potential to increase readership and advertising, covering costs and maintaining profits. Unfortunately, this business model has for the most part failed. Many higher quality news agencies are now implementing paywalls on their news websites to once again monetize their product. Others have begun to emulate the look and feel of tabloid news websites to increase readership and stickiness and advertising revenue. This study shows the negative impact of such visual tabloidization on initial impressions of credibility, which may have long term detrimental effects on the news agency.

The authors would like to dedicate this paper to the memory of Professor Séamus "Shay" Lawless, the supervisor of this work who died on May 16th 2019 after fulfilling his dream of summiting Mount Everest.

Informing the Design of a Personalized Privacy Assistant for the Internet of Things

Internet of Things (IoT) devices create new ways through which personal data is collected and processed by service providers. Frequently, end users have little awareness of, and even less control over, these devices' data collection. IoT Personalized Privacy Assistants (PPAs) can help overcome this issue by helping users discover and, when available, control the data collection practices of nearby IoT resources. We use semi-structured interviews with 17 participants to explore user perceptions of three increasingly more autonomous potential implementations of PPAs, identifying benefits and issues associated with each implementation. We find that participants weigh the desire for control against the fear of cognitive overload. We recommend solutions that address users' differing automation preferences and reduce notification overload. We discuss open issues related to opting out from public data collections, automated consent, the phenomenon of user resignation, and designing PPAs with at-risk communities in mind.

Snapstream: Snapshot-based Interaction in Live Streaming for Visual Art

Live streaming visual art such as drawing or using design software is gaining popularity. An important aspect of live streams is the direct and real-time communication between streamers and viewers. However, currently available text-based interaction limits the expressiveness of viewers as well as streamers, especially when they refer to specific moments or objects in the stream. To investigate the feasibility of using snapshots of streamed content as a way to enhance streamer-viewer interaction, we introduce Snapstream, a system that allows users to take snapshots of the live stream, annotate them, and share the annotated snapshots in the chat. Streamers can also verbally reference a specific snapshot during streaming to respond to viewers' questions or comments. Results from live deployments show that participants communicate more expressively and clearly with increased engagement using Snapstream. Participants used snapshots to reference part of the artwork, give suggestions on it, make fun images or memes, and log intermediate milestones. Our findings suggest that visual interaction enables richer experiences in live streaming.

Preparing for the Unexpected: Community Framework for Social Media Use and Social Support by Trail Thru-Hikers

A months-long hike of the Appalachian Trail often involve long-term preparation and life-altering decisions. Would-be hikers leverage institutional knowledge from literature and online forums to physically and mentally prepare for such an arduous hike. Their use of social platforms provide useful insights on motivations for undertaking the thru-hike, how they deal with unexpected conditions on the trail and understand choices made in conditions of scarcity. By analyzing over 100,000 Reddit posts and comments in r/AppalachianTrail and applying a Sense of Community theory, we sought to understand hikers' identity as community members, how their emotional and practical needs are met, and how they evolve. We found that the role and language of thru-hikers change as they progress from pre-hike, on-hike, and post-hike stages, from a questioner early on, to an expert post-hike. We conclude with design recommendations to support offline communities online.

Critical Race Theory for HCI

The human-computer interaction community has made some efforts toward racial diversity, but the outcomes remain meager. We introduce critical race theory and adapt it for HCI to lay a theoretical basis for race-conscious efforts, both in research and within our community. Building on the theory's original tenets, we argue that racism is pervasive in everyday socio-technical systems; that the HCI community is prone to "interest convergence", where concessions to inclusion require benefits to those in power; and that the neoliberal underpinnings of the technology industry itself propagate racism. Critical race theory uses storytelling as a means to upend deep-seated assumptions, and we relate several personal stories to highlight ongoing problems of race in HCI. The implications: all HCI research must be attuned to issues of race; participation of underrepresented minorities must be sought in all of our activities; and as a community, we cannot become comfortable while racial disparities exist.

Exploring Eyes-free Bezel-initiated Swipe on Round Smartwatches

Bezel-based gestures expand the interaction space of touch-screen devices (e.g., smartphones and smartwatches). Existing works have mainly focused on bezel-initiated swipe (BIS) on square screens. To investigate the usability of BIS on round smartwatches, we design six different circular bezel layouts, by dividing the bezel into 6, 8, 12, 16, 24, and 32 segments. We evaluate the user performance of BIS on these layouts in an eyes-free situation. The results show that the performance of BIS is highly orientation dependent, and varies significantly among users. Using the Support-Vector-Machine (SVM) model significantly increases the accuracy on 6-, 8-, 12-, and 16-segment layouts. We then compare the performance of personal and general SVM models, and find that personal models significantly improve the accuracy for 8-, 12-, 16-, and 24-segment layouts. Lastly, we discuss the potential smartwatch applications enabled by the BIS.

The Low/High Index of Pupillary Activity

A novel eye-tracked measure of pupil diameter oscillation is derived as an indicator of cognitive load. The new metric, termed the Low/High Index of Pupillary Activity (LHIPA), is able to discriminate cognitive load (vis-a-vis task difficulty) in several experiments where the Index of Pupillary Activity fails to do so. Rationale for the LHIPA is tied to the functioning of the human autonomic nervous system yielding a hybrid measure based on the ratio of Low/High frequencies of pupil oscillation. The paper's contribution is twofold. First, full documentation is provided for the calculation of the LHIPA. As with the IPA, it is possible for researchers to apply this metric to their own experiments where a measure of cognitive load is of interest. Second, robustness of the LHIPA is shown in analysis of three experiments, a restrictive fixed-gaze number counting task, a less restrictive fixed-gaze n-back task, and an applied eye-typing task.

Capturing Experts' Mental Models to Organize a Collection of Haptic Devices: Affordances Outweigh Attributes

Humans rely on categories to mentally organize and understand sets of complex objects. One such set, haptic devices, has myriad technical attributes that affect user experience in complex ways. Seeking an effective navigation structure for a large online collection, we elicited expert mental categories for grounded force-feedback haptic devices: 18 experts (9 device creators, 9 interaction designers) reviewed, grouped, and described 75 devices according to their similarity in a custom card-sorting study. From the resulting quantitative and qualitative data, we identify prominent patterns of tagging versus binning, and we report 6 uber-attributes that the experts used to group the devices, favoring affordances over device specifications. Finally, we derive 7 device categories and 9 subcategories that reflect the imperfect yet semantic nature of the expert mental models. We visualize these device categories and similarities in the online haptic collection, and we offer insights for studying expert understanding of other human-centered technology.

Supporting Self-Injury Recovery: The Potential for Virtual Reality Intervention

In this paper, we explore the use of virtual reality (VR) in assisting individuals who self-injure. Past work on self-injury in HCI has focused almost exclusively on mobile applications and message boards. As VR systems become more common, it is worth exploring what unique affordances of the technology can be leveraged to support self-injury reduction and cessation. Research on VR intervention and self-injury treatment informed the design of three novel virtual reality experiences. Nineteen interviews were conducted with individuals with current, or a past history of, self-injury with the goals of uncovering overall impressions of the perceived efficacy of VR with this population, as well as better understanding key mechanisms which impact their experience. Our analysis reveals four key elements common across all experiences: transportation, embodiment, immersion/distraction, and sense of control, and additional themes within each unique experience. We discuss the implications of these findings for future intervention design.

Learning from Positive Adaptations of Pediatric Cancer Patients to Design Health Technologies

The diagnosis of cancer brings about significant changes in the life of a child. In addition to physical pain, pediatric patients face psychological and social challenges. At the same time, some patients also have positive experiences with and attitudes toward their illness and treatment. Drawing on 19 semi-structured interviews with pairs of pediatric cancer patients and their parental caregivers, we examined patients' perspectives on their experience of living with cancer. We identified four salient themes in patients' positive experiences: future-oriented thinking, developing strong personal bonds and relationships, gaining knowledge and life experience, and developing self-management and coping skills. Collectively, the patients' positive experiences indicate that they adapt to their new lives through an evolving process. Based on this process, we provide design implications for health technologies to support and promote positive experiences during illness and treatment.

Pedestrian Detection with Wearable Cameras for the Blind: A Two-way Perspective

Blind people have limited access to information about their surroundings, which is important for ensuring one's safety, managing social interactions, and identifying approaching pedestrians. With advances in computer vision, wearable cameras can provide equitable access to such information. However, the always-on nature of these assistive technologies poses privacy concerns for parties that may get recorded. We explore this tension from both perspectives, those of sighted passersby and blind users, taking into account camera visibility, in-person versus remote experience, and extracted visual information. We conduct two studies: an online survey with MTurkers (N=206) and an in-person experience study between pairs of blind (N=10) and sighted (N=40) participants, where blind participants wear a working prototype for pedestrian detection and pass by sighted participants. Our results suggest that both of the perspectives of users and bystanders and the several factors mentioned above need to be carefully considered to mitigate potential social tensions.

Urban Mosaic: Visual Exploration of Streetscapes Using Large-Scale Image Data

Urban planning is increasingly data driven, yet the challenge of designing with data at a city scale and remaining sensitive to the impact at a human scale is as important today as it was for Jane Jacobs. We address this challenge with Urban Mosaic, a tool for exploring the urban fabric through a spatially and temporally dense data set of 7.7 million street-level images from New York City, captured over the period of a year. Working in collaboration with professional practitioners, we use Urban Mosaic to investigate questions of accessibility and mobility, and preservation and retrofitting. In doing so, we demonstrate how tools such as this might provide a bridge between the city and the street, by supporting activities such as visual comparison of geographically distant neighborhoods, and temporal analysis of unfolding urban development.

Let's Talk about Sext: How Adolescents Seek Support and Advice about Their Online Sexual Experiences

We conducted a thematic content analysis of 4,180 posts by adolescents (ages 12-17) on an online peer support mental health forum to understand what and how adolescents talk about their online sexual interactions. Youth used the platform to seek support (83%), connect with others (15%), and give advice (5%) about sexting, their sexual orientation, sexual abuse, and explicit content. Females often received unwanted nudes from strangers and struggled with how to turn down sexting requests from people they knew. Meanwhile, others who sought support complained that they received unwanted sexual solicitations while doing so-to the point that adolescents gave advice to one another on which users to stay away from. Our research provides insight into the online sexual experiences of adolescents and how they seek support around these issues. We discuss how to design peer-based social media platforms to support the well-being and safety of youth.

See, Feel, Move: Player Behaviour Analysis through Combined Visualization of Gaze, Emotions, and Movement

Playtesting of games often relies on a mixed-methods approach to obtain more holistic insights about and, in turn, improve the player experience. However, triangulating the different data sources and visualizing them in an integrated manner such that they contextualize each other still proves challenging. Despite its potential value for gauging player behaviour, this area of research continues to be underexplored. In this paper, we propose a visualization approach that combines commonly tracked movement data with - from a visualization perspective rarely considered - gaze behaviour and emotional responses. We evaluated our approach through a qualitative expert study with five professional game developers. Our results show that both the individual visualization of gaze, emotions, and movement but especially their combination are valuable to understand and form hypotheses about player behaviour. At the same time, our results stress that careful attention needs to be paid to ensure that the visualization remains legible and does not obfuscate information.

Exploring Human-Robot Interaction with the Elderly: Results from a Ten-Week Case Study in a Care Home

Ageing societies and the associated pressure on the care systems are major drivers for new developments in socially assistive robotics. To understand better the real-world potential of robot-based assistance, we undertook a 10-week case study in a care home involving groups of residents, caregivers and managers as stakeholders. We identified both, enablers and barriers to the potential implementation of robot systems. The study employed the robot platform Pepper, which was deployed with a view to understanding better multi-domain interventions with a robot supporting physical activation, cognitive training and social facilitation. We employed the robot in a group setting in a care facility over the course of 10 weeks and 20 sessions, observing how stakeholders, including residents and caregivers, appropriated, adapted to, and perceived the robot. We also conducted interviews with 11 residents and caregivers. Our results indicate that the residents were positively engaged in the training sessions that were moderated by the robot. The study revealed that such humanoid robots can work in a care home but that there is a moderating person needed, that is in control of the robot.

Improving Worker Engagement Through Conversational Microtask Crowdsourcing

The rise in popularity of conversational agents has enabled humans to interact with machines more naturally. Recent work has shown that crowd workers in microtask marketplaces can complete a variety of human intelligence tasks (HITs) using conversational interfaces with similar output quality compared to the traditional Web interfaces. In this paper, we investigate the effectiveness of using conversational interfaces to improve worker engagement in microtask crowdsourcing. We designed a text-based conversational agent that assists workers in task execution, and tested the performance of workers when interacting with agents having different conversational styles. We conducted a rigorous experimental study on Amazon Mechanical Turk with 800 unique workers, to explore whether the output quality, worker engagement and the perceived cognitive load of workers can be affected by the conversational agent and its conversational styles. Our results show that conversational interfaces can be effective in engaging workers, and a suitable conversational style has potential to improve worker engagement.

"Person, Shoes, Tree. Is the Person Naked?" What People with Vision Impairments Want in Image Descriptions

Access to digital images is important to people who are blind or have low vision (BLV). Many contemporary image description efforts do not take into account this population's nuanced image description preferences. In this paper, we present a qualitative study that provides insight into 28 BLV people's experiences with descriptions of digital images from news websites, social networking sites/platforms, eCommerce websites, employment websites, online dating websites/platforms, productivity applications, and e-publications. Our findings reveal how image description preferences vary based on the source where digital images are encountered and the surrounding context. We provide recommendations for the development of next-generation image description technologies inspired by our empirical analysis.

Utilizing VR and Gaze Tracking to Develop AR Solutions for Industrial Maintenance

Augmented reality (AR) presents a variety of possibilities for industrial maintenance. However, the development of real-world AR solutions has been limited due to the technological capabilities and uncertainty with respect to safety at deployment. We introduce the approach of using AR simulation in virtual reality (VR) coupled with gaze tracking to enable resource-efficient AR development. We tested in-field AR guidance and safety awareness features in an iterative development-evaluation process with experts from the elevator maintenance industry. We further conducted a survey, utilizing actual gaze data from the evaluation to elicit comments from industry experts on the usefulness of AR simulation and gaze tracking. Our results show the potential of AR within VR approach combined with gaze tracking. With this framework, AR solutions can be iteratively and safely tested without actual implementation, while gaze data provide advanced objective means to evaluate the designed AR content, documentation usage, and safety awareness.

Evaluating Smartwatch-based Sound Feedback for Deaf and Hard-of-hearing Users Across Contexts

We present a qualitative study with 16 deaf and hard of hearing (DHH) participants examining reactions to smartwatch-based visual + haptic sound feedback designs. In Part 1, we conducted a Wizard-of-Oz (WoZ) evaluation of three smartwatch feedback techniques (visual alone, visual + simple vibration, and visual + tacton) and investigated vibrational patterns (tactons) to portray sound loudness, direction, and identity. In Part 2, we visited three public or semi-public locations where we demonstrated sound feedback on the smartwatch in situ to examine contextual influences and explore sound filtering options. Our findings characterize uses for vibration in multimodal sound awareness, both for push notification and for immediately actionable sound information displayed through vibrational patterns (tactons). In situ experiences caused participants to request sound filtering - particularly to limit haptic feedback - as a method for managing soundscape complexity. Additional concerns arose related to learnability, possibility of distraction, and system trust. Our findings have implications for future portable sound awareness systems.

Play-Based Design: Giving 3- to 4-Year-Old Children a Voice in the Design Process

There has been a dramatic growth in interactive technology use by children under the age of 5 during the past decade. Despite this growth, children under the age of 5 typically participate only as users or testers in the design process in the overwhelming majority of projects targeting this population presented in key child-computer interaction venues. In this paper we introduce play-based design, an age-appropriate design method to give 3-4-year-old children a voice in the design process. More specifically, we contribute a thorough analysis of the use of existing methods to design technologies for children under the age of 5, a summary of the process that resulted in the development of play-based design, a detailed description of play-based design, a qualitative analysis of our experience implementing play-based design with two groups of children, and a discussion of play-based design's place among other methods, its advantages, and limitations.

ElastOscillation: 3D Multilevel Force Feedback for Damped Oscillation on VR Controllers

Force feedback from damped oscillation is a common effect in our daily lives, especially when shaking an elastic object, an object hanging or containing other stuff, or a container with liquid, e.g., casting with a fishing pole or wine-swirling. Such a force, affected by complex physical variations and collisions, is difficult to properly simulate using current force feedback methods. Therefore, we propose ElastOscillation on a virtual reality (VR) controller to provide 3D multilevel force feedback for damped oscillation to enhance VR experiences. ElastOscillation consists of a proxy, six elastic bands and DC motors. It leverages the motors to control the bands' elasticity to restrain the movement of the proxy, which is connected with the bands. Therefore, when users shake the ElastOscillation device, the proxy shakes or moves in corresponding ranges of movement. The users then perceive the force from oscillation at different levels. In addition, elastic force from the bands further reinforces the oscillation force feedback. We conducted a force perception study to understand users' distinguishability for perceiving oscillation forces in 1D and 2D movement, respectively. Based on the results, we performed a VR experience study to show that the force feedback provided by ElastOscillation enhances VR realism.

Levitation Simulator: Prototyping Ultrasonic Levitation Interfaces in Virtual Reality

We present the Levitation Simulator, a system that enables researchers and designers to iteratively develop and prototype levitation interface ideas in Virtual Reality. This includes user tests and formal experiments. We derive a model of the movement of a levitating particle in such an interface. Based on this, we develop an interactive simulation of the levitation interface in VR, which exhibits the dynamical properties of the real interface. The results of a Fitts' Law pointing study show that the Levitation Simulator enables performance, comparable to the real prototype. We developed the first two interactive games, dedicated for levitation interfaces: LeviShooter and BeadBounce, in the Levitation Simulator, and then implemented them on the real interface. Our results indicate that participants experienced similar levels of user engagement when playing the games, in the two environments. We share our Levitation Simulator as Open Source, thereby democratizing levitation research, without the need for a levitation apparatus.

Crafting Personal Information - Resistance, Imperfection, and Self-Creation in Bullet Journaling

Bullet journals are hand-written and self-created combinations of calendar, journal and planner. Central to this practice is how personal information is managed through a craft-based process. Based on a qualitative study, we discuss a set of themes that emerged in our analysis of this practice. We discuss how open-ended use of various materials for crafting of personal information engages in: 1) deliberate and strategic boundary work of what information to include and how combinations of data provide holistic and novel views of practitioner's life situations; 2) processes of self-creation and reflection on personal life trajectories; 3) appreciation of ourselves and the world around us as imperfect; and 4) ways of resisting the "business-like efficiency" that come with the large quantities of information that permeate contemporary life. We propose that this opens up new directions for thinking about how technologies of personal information may come into play in people's lives.

Companionship Is Not a Function: The Effect of a Novel Robotic Object on Healthy Older Adults' Feelings of "Being-Seen"

One of the challenges faced by healthy older adults is experiencing feelings of not "being-seen". Companion robots, commonly designed with zoomorphic or humanoid appearance show success among clinical older adults, but healthy older adults find them degrading. We present the design and implementation of a novel non-humanoid robot. The robot's primary function is a cognitive word game. Social interaction is conveyed as a secondary function, using non-verbal gestures, inspired by dancers' movement. In a lab study, 39 healthy older adults interacted with the prototype in 3 conditions: Companion-Function; Game-Function; and No-Function. Results show the non-verbal gestures were associated with feelings of "being-seen", and willingness to accept the robot into their home was influenced by its function, with game significantly higher than companion. We conclude that robot designers should further explore the potential of non-humanoid robots as a new class of companion robots, with a primary function that is not companionship.

GPkit: A Human-Centered Approach to Convex Optimization in Engineering Design

We present GPkit, a Python toolkit for Geometric and Signomial Programming that prioritizes explainability and incremental complexity. GPkit was designed through an ethnographic approach in the firms, classrooms, and research labs where it became part of the fabric of daily engineering work. Organizations have approached GPkit both in ways which centralize and in ways which distribute design work, usecases which emerged from and inspired new toolkit features. This two-way flow between mathematical structure and practitioner knowledge resulted in several novel contributions to the formulation and interpretation of convex programs and to our understanding of early-stage engineering design. For example, dual solutions (often considered incidental) can be more valuable to a design process than the "optimal design" itself, and we present novel algorithms and design methods based on this insight.

Designing Games for Healthy Sleep

A sleep deficit has far-reaching consequences, but for many people, healthy sleep is not a priority or a possibility. We explore the potential for "sleepy games" as a genre of transformational games. To explore this design space, we prototyped nine games through an iterative design process. Based on analysis of design decisions and the games as artifacts, we identify seven design challenges for sleepy games: agency and control; physiological and mental arousal; intervention timing; social embeddedness; multisensory experience; vulnerability; and identity and values. We expand on three games with playtesting to show how these design challenges unfold for players in practice, show the impact on players' lives, and discuss sleepy games as creative, social, and situated practices.

Learning Through Exploration: How Children, Adults, and Older Adults Interact with a New Feature-Rich Application

Feature-rich applications such as word processors and spreadsheets are not only being used by adults but increasingly by children and older adults as well. Learning these applications is challenging as they offer hundreds of commands throughout the interface. We investigate how newcomers from different age groups explore the user interface of a feature-rich application to determine, locate, and use relevant features. We conducted an in-lab observational study with 10 children (10-12), 10 adults (20-35) and 10 older adults (60-75) who were first-time users of Microsoft OneNote. Our results illustrate key exploration differences across age groups, including that children were careful and performed as efficiently as the adults, whereas older adults spent a longer time and repeated sequences of failed selections. Further, their exploration style was negatively influenced by their past knowledge of similar applications. We discuss design interventions to accommodate these exploration differences and to improve software onboarding for newcomers.

Taking Data Out of Context to Hyper-Personalize Ads: Crowdworkers' Privacy Perceptions and Decisions to Disclose Private Information

Data brokers and advertisers increasingly collect data in one context and use it in another. When users encounter a misuse of their data, do they subsequently disclose less information? We report on human-subjects experiments with 25 in-person and 280 online participants. First, participants provided personal information amidst distractor questions. A week later, while participants completed another survey, they received either a robotext or online banner ad seemingly unrelated to the study. Half of the participants received an ad containing their name, partner's name, preferred cuisine, and location; others received a generic ad. We measured how many of 43 potentially invasive questions participants subsequently chose to answer. Participants reacted negatively to the personalized ad, yet answered nearly all invasive questions accurately. We unpack our results relative to the privacy paradox, contextual integrity, and power dynamics in crowdworker platforms.

What Are You Talking To?: Understanding Children's Perceptions of Conversational Agents

Conversational agents (CAs) available in smart phones or smart speakers play an increasingly important role in young children's technological landscapes and life worlds. While a handful of studies have documented children's natural interactions with CAs, little is known about children's perceptions of CAs. To fill this gap, we examined three- to six-year-olds' perceptions of CAs' animate/artifact domain membership and properties, as well as their justifications for these perceptions. We found that children sometimes take a more nuanced position and spontaneously attribute both artifact and animate properties to CAs or view them as neither artifacts nor animate objects. This study extends current research on children's perceptions of intelligent artifacts by adding CAs as a new genre of study and provides some underlying knowledge that may guide the development of CAs to support young children's cognitive and social development.

Moving Toward an Ecologically Valid Data Collection Protocol for 2D Gestures In Video Games

Those who design gesture recognizers and user interfaces often use data collection applications that enable users to comfortably produce gesture training samples. In contrast, games present unique contexts that impact cognitive load and have the potential to elicit rapid gesticulations as players react to dynamic conditions, which can result in high gesture form variability. However, the extent to which these gestures differ is presently unknown. To this end, we developed two games with unique mechanics, Follow the Leader (FTL) and Sleepy Town, as well as a standard data collection application. We collected gesture samples from 18 participants across all conditions for gestures of varying complexity, and through an analysis using relative, global, and distribution coverage measures, we confirm significant differences between conditions. We discuss the implications of our findings, and show that our FTL design is closer to being an ecologically valid data collection protocol with low implementation complexity.

Toward Automated Feedback on Teacher Discourse to Enhance Teacher Learning

Like anyone, teachers need feedback to improve. Due to the high cost of human classroom observation, teachers receive infrequent feedback which is often more focused on evaluating performance than on improving practice. To address this critical barrier to teacher learning, we aim to provide teachers with detailed and actionable automated feedback. Towards this end, we developed an approach that enables teachers to easily record high-quality audio from their classes. Using this approach, teachers recorded 142 classroom sessions, of which 127 (89%) were usable. Next, we used speech recognition and machine learning to develop teacher-generalizable computer-scored estimates of key dimensions of teacher discourse. We found that automated models were moderately accurate when compared to human coders and that speech recognition errors did not influence performance. We conclude that authentic teacher discourse can be recorded and analyzed for automatic feedback. Our next step is to incorporate the automatic models into an interactive visualization tool that will provide teachers with objective feedback on the quality of their discourse.

Inducing and Mitigating Stereotype Threat Through Gendered Virtual Body-Swap Illusions

A psychological phenomenon termed "stereotype threat" has been shown to contribute to women's underperformance and underrepresentation in math and science fields. Within the virtual reality literature, a recent study utilized gendered body-swap illusions (i.e., women in male virtual bodies) to mitigate the effects of stereotype threat among a sample of female participants. The present research provides a much needed replication of this intervention, as well as a critical extension of virtual reality research on the Proteus Effect to test whether stereotype threat can be induced among male participants immersed in a female virtual body. Results supported both the replication and extension hypotheses; female participants embodied in male avatars were buffered from stereotype threat whereas male participants embodied in female avatars suffered from stereotype threat. Avatar gender also influenced participants' math confidence and awareness of the negative societal stereotype regarding women's math ability.

Surfacing Visualization Mirages

Dirty data and deceptive design practices can undermine, invert, or invalidate the purported messages of charts and graphs. These failures can arise silently: a conclusion derived from a particular visualization may look plausible unless the analyst looks closer and discovers an issue with the backing data, visual specification, or their own assumptions. We term such silent but significant failures . We describe a conceptual model of mirages and show how they can be generated at every stage of the visual analytics process. We adapt a methodology from software testing, , as a way of automatically surfacing potential mirages at the visual encoding stage of analysis through modifications to the underlying data and chart specification. We show that metamorphic testing can reliably identify mirages across a variety of chart types with relatively little prior knowledge of the data or the domain.

FoodFab: Creating Food Perception Illusions using Food 3D Printing

Personalization of eating such that everyone consumes only what they need allows improving our management of food waste. In this paper, we explore the use of food 3D printing to create perceptual illusions for controlling the level of perceived satiety given a defined amount of calories. We present FoodFab, a system that allows users to control their food intake through modifying a food's internal structure via two 3D printing parameters: infill pattern and infill density. In two experiments with a total of 30 participants, we studied the effect of these parameters on users' chewing time that is known to affect people's feeling of satiety. Our results show that we can indeed modify the chewing time by varying infill pattern and density, and thus control perceived satiety. Based on the results, we propose two computational models and integrate them into a user interface that simplifies the creation of personalized food structures.

Collaborative Writing Across Multiple Artifact Ecologies

Research focusing on how collaborative writing takes place across multiple applications and devices and over longer projects is sparse. We respond to this gap by presenting the results of a qualitative study of longer-term academic writing projects, showing how co-writers employ multiple tools when working on a common text. We identify three patterns of multi-application collaboration as well as four common types of motivations for transitions between applications. We also extend existing taxonomies of collaborative writing by proposing a categorization of the functions served by the text as object and backbone of the collaboration. Together, these contributions offer a framing for understanding transitions within and across artifact ecologies in work around a common object. Our findings highlight ways in which features like concurrent editing may in fact challenge the collaborative writing process, and we point to opportunities for alternative application models.

Enemy Within: Long-term Motivation Effects of Deep Player Behavior Models for Dynamic Difficulty Adjustment

Balancing games and producing content that remains interesting and challenging is a main cost factor in the design and maintenance of games. Dynamic difficulty adjustments (DDA) can successfully tune challenge levels to player abilities, but when implemented with classic heuristic parameter tuning (HPT) often turns out to be very noticeable, e.g. as "rubber-banding". Deep learning techniques can be employed for deep player behavior modeling (DPBM), enabling more complex adaptivity, but effects over frequent and longer-lasting game engagements, as well as how it compares to HPT has not been empirically investigated. We present a situated study of the effects of DDA via DPBM as compared to HPT on intrinsic motivation, perceived challenge and player motivation in a real-world MMORPG. The results indicate that DPBM can lead to significant improvements in intrinsic motivation and players prefer game experience episodes featuring DPBM over experience episodes with classic difficulty management.

Random, Messy, Funny, Raw: Finstas as Intimate Reconfigurations of Social Media

Among many young people, the creation of a finsta-a portmanteau of "fake" and "Instagram" which describes secondary Instagram accounts-provides an outlet to share emotional, low-quality, or indecorous content with their close friends. To study why people create and maintain finstas, we conducted a qualitative study through interviews with finsta users and content analysis of video bloggers exposing their finsta on YouTube. We found that one way that young people deal with mounting social pressures is by reconfiguring online platforms and changing their purposes, norms, expectations, and currencies. Carving out smaller spaces accessible only to close friends allows users the opportunity for a more unguarded, vulnerable, and unserious performance. Drawing on feminist theory, we term this process intimate reconfiguration. Through this reconfiguration finsta users repurpose an existing and widely-used social platform to create opportunities for more meaningful and reciprocal forms of social support.

Jubilee: An Extensible Machine for Multi-tool Fabrication

We present Jubilee, an open-source hardware machine with automatic tool-changing and interchangeable bed plates. As digital fabrication tools have become more broadly accessible, tailoring those machines to new users and novel workflows has become central to HCI research. However, the lack of hardware infrastructure makes custom application development cumbersome. We identify a need for an extensible platform to allow HCI researchers to develop workflows for fabrication, material exploration, and other applications. Jubilee addresses this need. It can automatically and repeatably change tools in the same operation. It can be built with a combination of simple 3D-printed and readily available parts. It has several standard head designs for a variety of applications including 3D printing, syringe-based liquid handling, imaging, and plotting. We present Jubilee with a comprehensive set of assembly instructions and kinematic mount templates for user-designed tools and bed plates. Finally we demonstrate Jubilee's multi-tool workflow functionality with a series of example applications.

Using Diaries to Probe the Illness Experiences of Adolescent Patients and Parental Caregivers

Adolescents with chronic conditions must work with family caregivers to manage their illness experiences. To explore how technology can support collaborative documentation of these experiences, we designed and distributed a paper diary probe kit in a two-week field deployment with 12 adolescent-parent dyads (24 participants). Three insights emerged from the study that highlight how technology can support shared illness management: 1) provide scaffolds to recognize physical and emotional experiences in the context of daily activities; 2) help families reconstruct patient experiences; and 3) adapt to individual preferences for capturing, representing and sharing experiences. We discuss opportunities for HCI research that follow from these findings and conclude by reflecting on the benefits and limitations of using diary probes with adolescent patients and their parental caregivers.

Soundr: Head Position and Orientation Prediction Using a Microphone Array

Although state-of-the-art smart speakers can hear a user's speech, unlike a human assistant these devices cannot figure out users' verbal references based on their head location and orientation. Soundr presents a novel interaction technique that leverages the built-in microphone array found in most smart speakers to infer the user's spatial location and head orientation using only their voice. With that extra information, Soundr can figure out users references to objects, people, and locations based on the speakers' gaze, and also provide relative directions. To provide training data for our neural network, we collected 751 minutes of data (50x that of the best prior work) from human speakers leveraging a virtual reality headset to accurately provide head tracking ground truth. Our results achieve an average positional error of 0.31m and an orientation angle accuracy of 34.3° for each voice command. A user study to evaluate user preferences for controlling IoT appliances by talking at them found this new approach to be fast and easy to use.

Crowdsourcing the Perception of Machine Teaching

Teachable interfaces can empower end-users to attune machine learning systems to their idiosyncratic characteristics and environment by explicitly providing pertinent training examples. While facilitating control, their effectiveness can be hindered by the lack of expertise or misconceptions. We investigate how users may conceptualize, experience, and reflect on their engagement in machine teaching by deploying a mobile teachable testbed in Amazon Mechanical Turk. Using a performance-based payment scheme, Mechanical Turkers (N=100) are called to train, test, and re-train a robust recognition model in real-time with a few snapshots taken in their environment. We find that participants incorporate diversity in their examples drawing from parallels to how humans recognize objects independent of size, viewpoint, location, and illumination. Many of their misconceptions relate to consistency and model capabilities for reasoning. With limited variation and edge cases in testing, the majority of them do not change strategies on a second training attempt.

High Water Pants: Designing Embodied Environmental Speculation

In this paper, we present the High Water Pants: speculative wearable technology which makes climate change tangible for everyday cyclists. The pants work by mechanically shortening when a cyclist wearing the pants enters an area of Seattle, USA, which is projected to be impacted by sea-level rise in 30-80 years. This interaction 'bends time' by allowing cyclists to feel future climate change data in the present. First, we discuss the research through design process of creating the High Water Pants including foundational research, a description of the design concept and results of a preliminary study with the pants. Second, we discuss three implications of the pants for human-computer interaction (HCI): (1) they offer the concept of a 'present/future' paradigm for embodied speculation, (2) our research process demonstrates how to successfully involve more-than-human perspectives, and (3) we articulate how the High Water Pants respond to shifts in HCI's framing of sustainability.

The Designer's Body as Resource in Design: Exploring Combinations of Point-of-view and Tense

The design of wearable, tangible and embedded interactive products requires a focus on bodily/kinesthetic aspects of the user experience, that is, how the product "feels" in use. Although best practice in user-centered design (such as iterative design, prototyping, user testing) also applies for this new type of product, the designer's skill set needs to be supplemented with design methods and practices that utilize bodily intelligence and empathy with the user. We present a framework for categorizing such body-centered design practices based on two dimensions: point-of-view (1st, 2nd, 3rd person) and tense (past, present, future). Inspired by Merleau-Ponty's phenomenology of the body, Shusterman's work on somaesthetics, and Buber's theories on intersubjectivity, the framework provides a language for talking about different ways designers and co-designers can utilize their body as a design resource. The intention is not to be prescriptive on method, but to provide guidance during planning, execution and analysis.

Molder: An Accessible Design Tool for Tactile Maps

Tactile materials are powerful teaching aids for students with visual impairments (VIs). To design these materials, designers must use modeling applications, which have high learning curves and rely on visual feedback. Today, Orientation and Mobility (O&M) specialists and teachers are often responsible for designing these materials. However, most of them do not have professional modeling skills, and many are visually impaired themselves. To address this issue, we designed Molder, an accessible design tool for interactive tactile maps, an important type of tactile materials that can help students learn O&M skills. A designer uses Molder to design a map using tangible input techniques, and Molder provides auditory feedback and high-contrast visual feedback. We evaluated Molder with 12 participants (8 with VIs, 4 sighted). After a 30-minute training session, the participants were all able to use Molder to design maps with customized tactile and interactive information.

Approach Matters: Linking Practitioner Approaches to Technology Design for People with Dementia

Technology design for dementia is an active and growing area. Though work to date has largely addressed functional needs, there is a growing recognition of the importance of supporting meaningful activities. However, technology for active, rather than passive, engagement is relatively novel beyond specific applications (e.g., music or reminiscence therapy). To better understand how to support active engagement of people with dementia in activities, we interviewed nineteen practitioners. Our findings reveal differing approaches to making sense of the actions of people with dementia, as well as to engaging them in activities. We discuss the importance of tracing epistemological understandings of dementia to different configurations of technology for people living with dementia and provide a practical guide to support designers to do so. Finally, we discuss considerations for the design of dementia technologies around facilitating self-actualization and managing emotional exposure for care-providers.

Designing and Evaluating 'In the Same Boat', A Game of Embodied Synchronization for Enhancing Social Play

Social closeness is important for health and well-being, but is difficult to maintain over a distance. Games can help connect people by strengthening existing relationships or creating new ones through shared playful experiences. We present the design and evaluation of 'In the Same Boat' (ITSB), a two-player infinite runner designed to foster social closeness in distributed dyads. ITSB leverages the synchronization of both players' input to steer a canoe down a river and avoid obstacles. We created two versions: embodied controls, which use players' physiological signals (breath rate, facial expressions), and standard keyboard controls. Results from a study with 35 dyads indicate that ITSB fostered affiliation, and while embodied controls were less intuitive, people enjoyed them more. Further, photos of the dyads were rated as happier and closer in the embodied condition, indicating the potential of embodied controls to foster social closeness in synchronized play over a distance.

Camera Adversaria

In this paper we introduce Camera Adversaria; a mobile app designed to disrupt the automatic surveillance of personal photographs by technology companies. The app leverages the brittleness of deep neural networks with respect to high-frequency signals, adding generative adversarial perturbations to users' photographs. These perturbations confound image classification systems but are virtually imperceptible to human viewers. Camera Adversaria builds on methods developed by machine learning researchers as well as a growing body of work, primarily from art and design, which transgresses contemporary surveillance systems. We map the design space of responses to surveillance and identify an under-explored region where our project is situated. Finally we show that the language typically used in the adversarial perturbation literature serves to affirm corporate surveillance practices and malign resistance. This raises significant questions about the function of the research community in countenancing systems of surveillance.

How Well Do People Report Time Spent on Facebook?: An Evaluation of Established Survey Questions with Recommendations

Many studies examining social media use rely on self-report survey questions about how much time participants spend on social media platforms. Because they are challenging to answer accurately and susceptible to various biases, these self-reported measures are known to contain error -- although the specific contours of this error are not well understood. This paper compares data from ten self-reported Facebook use survey measures deployed in 15 countries (N = 49,934) against data from Facebook's server logs to describe factors associated with error in commonly used survey items from the literature. Self-reports were moderately correlated with actual Facebook use (r = 0.42 for the best-performing question), though participants significantly overestimated how much time they spent on Facebook and underestimated the number of times they visited. People who spent a lot of time on the platform were more likely to misreport their time, as were teens and younger adults, which is notable because of the high reliance on college-aged samples in many fields. We conclude with recommendations on the most accurate ways to collect time-spent data via surveys.

Augmenting Static Visualizations with PapARVis Designer

This paper presents an authoring environment for augmenting static visualizations with virtual content in augmented reality.Augmenting static visualizations can leverage the best of both physical and digital worlds, but its creation currently involves different tools and devices, without any means to explicitly design and debug both static and virtual content simultaneously. To address these issues, we design an environment that seamlessly integrates all steps of a design and deployment workflow through its main features: i) an extension to Vega, ii) a preview, and iii) debug hints that facilitate valid combinations of static and augmented content. We inform our design through a design space with four ways to augment static visualizations. We demonstrate the expressiveness of our tool through examples, including books, posters, projections, wall-sized visualizations. A user study shows high user satisfaction of our environment and confirms that participants can create augmented visualizations in an average of 4.63 minutes.

Temporal Segmentation of Creative Live Streams

Many artists broadcast their creative process through live streaming platforms like Twitch and YouTube, and people often watch archives of these broadcasts later for learning and inspiration. Unfortunately, because live stream videos are often multiple hours long and hard to skim and browse, few can leverage the wealth of knowledge hidden in these archives. We present an approach for automatic temporal segmentation of creative live stream videos. Using an audio transcript and a log of software usage, the system segments the video into sections that the artist can optionally label with meaningful titles. We evaluate this approach by gathering feedback from expert streamers and comparing automatic segmentations to those made by viewers. We find that, while there is no one "correct" way to segment a live stream, our automatic method performs similarly to viewers, and streamers find it useful for navigating their streams after making slight adjustments and adding section titles.

Outline Pursuits: Gaze-assisted Selection of Occluded Objects in Virtual Reality

In 3D environments, objects can be difficult to select when they overlap, as this affects available target area and increases selection ambiguity. We introduce Outline Pursuits which extends a primary pointing modality for gaze-assisted selection of occluded objects. Candidate targets within a pointing cone are presented with an outline that is traversed by a moving stimulus. This affords completion of the selection by gaze attention to the intended target's outline motion, detected by matching the user's smooth pursuit eye movement. We demonstrate two techniques implemented based on the concept, one with a controller as the primary pointer, and one in which Outline Pursuits are combined with head pointing for hands-free selection. Compared with conventional raycasting, the techniques require less movement for selection as users do not need to reposition themselves for a better line of sight, and selection time and accuracy are less affected when targets become highly occluded.

Engaging the Commons in Participatory Sensing: Practice, Problems, and Promise in the Context of Dockless Bikesharing

Participatory sensing refers to the sensing paradigm where human participants use personal mobile devices to generate and share data from their surroundings. It holds the promise of providing information that is otherwise challenging to access, which sets the stage for understanding and resolving various social issues. However, difficulties in engaging participants often hinder the fulfillment of this promise. The current paper presents a qualitative study in the context of dockless bikesharing, where participatory sensing constitutes a backbone of the bike status monitoring system. We conducted in-depth interviews with 30 participants. These participants came from different emergent groups who took part in filing status reports for shared bikes. Our analysis indicated close associations among participants' models of engagement, their perceived (dis)connections with the sensing data, and their situated interpretation of the incentives. Based on these findings, we propose ways to engage the commons in participatory sensing for dockless bikesharing and beyond.

Evaluating the End-User Experience of Private Browsing Mode

In this paper, we investigate why users of private browsing mode misunderstand the benefits and limitations of private browsing. We design and conduct a three-part study: (1) an analytic evaluation of the user interface of private mode in different browsers; (2) a qualitative user study to explore user mental models of private browsing; (3) a participatory design study to investigate why existing browser disclosures, the in-browser explanations of private mode, do not communicate the actual protection of private mode. We find the user interface of private mode in different browsers violated well-established design guidelines and heuristics. Further, most participants had incorrect mental models of private browsing, influencing their understanding and usage of private mode. We also find existing browser disclosures did not explain the primary security goal of private mode. Drawing from the results of our study, we extract a set of recommendations to improve the design of disclosures.

PalmBoard: Leveraging Implicit Touch Pressure in Statistical Decoding for Indirect Text Entry

We investigated how to incorporate implicit touch pressure, finger pressure applied to a touch surface during typing, to improve text entry performance via statistical decoding. We focused on one-handed touch-typing on indirect interface as an example scenario. We first collected typing data on a pressure-sensitive touchpad, and analyzed users' typing behavior such as touch point distribution, key-to-finger mappings, and pressure images. Our investigation revealed distinct pressure patterns for different keys. Based on the findings, we performed a series of simulations to iteratively optimize the statistical decoding algorithm. Our investigation led to a Markov-Bayesian decoder incorporating pressure image data into decoding. It improved the top-1 accuracy from 53% to 74% over a naive Bayesian decoder. We then implemented PalmBoard, a text entry method that implemented the Markov-Bayesian decoder and effectively supported one-handed touch-typing on indirect interfaces. A user study showed participants achieved an average speed of 32.8 WPM with 0.6% error rate. Expert typists could achieve 40.2 WPM with 30 minutes of practice. Overall, our investigation showed that incorporating implicit touch pressure is effective in improving text entry decoding.

Wrex: A Unified Programming-by-Example Interaction for Synthesizing Readable Code for Data Scientists

Data wrangling is a difficult and time-consuming activity in computational notebooks, and existing wrangling tools do not fit the exploratory workflow for data scientists in these environments. We propose a unified interaction model based on programming-by-example that generates readable code for a variety of useful data transformations, implemented as a Jupyter notebook extension called Wrex. User study results demonstrate that data scientists are significantly more effective and efficient at data wrangling with Wrex over manual programming. Qualitative participant feedback indicates that Wrex was useful and reduced barriers in having to recall or look up the usage of various data transform functions. The synthesized code allowed data scientists to verify the intended data transformation, increased their trust and confidence in Wrex, and fit seamlessly within their cell-based notebook workflows. This work suggests that presenting readable code to professional data scientists is an indispensable component of offering data wrangling tools in notebooks.

Automatic Annotation Synchronizing with Textual Description for Visualization

In this paper, we propose a technique for automatically annotating visualizations according to the textual description. In our approach, visual elements in the target visualization, along with their visual properties, are identified and extracted with a Mask R-CNN model. Meanwhile, the description is parsed to generate visual search requests. Based on the identification results and search requests, each descriptive sentence is displayed beside the described focal areas as annotations. Different sentences are presented in various scenes of the generated animation to promote a vivid step-by-step presentation. With a user-customized style, the animation can guide the audience's attention via proper highlighting such as emphasizing specific features or isolating part of the data. We demonstrate the utility and usability of our method through a user study with use cases.

Assessing Severity of Pulmonary Obstruction from Respiration Phase-Based Wheeze-Sensing Using Mobile Sensors

Obstructive pulmonary diseases cause limited airflow from the lung and severely affect patients' quality of life. Wheeze is one of the most prominent symptoms for them. High requirements imposed by traditional diagnosis methods make regular monitoring of pulmonary obstruction challenging, which hinders the opportunity of early intervention and prevention of significant exacerbation. In this work, we explore the feasibility of developing a mobile sensor-based system as a convenient means of assessing the severity of pulmonary obstruction via respiration phase-based symptomatic wheeze sensing. We conduct a 131 subjects' (91 patients and 40 healthy) study for the detection (F1: 87.96%) and characterization (F1: 79.47%) of wheeze. Subsequently, we develop novel wheeze metrics, which show a significant correlation (Pearson's correlation: -0.22, p-value: 0.024) with standard spirometry measure of pulmonary obstruction severity. This work takes a principal step towards the unobtrusive assessment of pulmonary condition from mobile sensor interactions.

Co-Designing Checklists to Understand Organizational Challenges and Opportunities around Fairness in AI

Many organizations have published principles intended to guide the ethical development and deployment of AI systems; however, their abstract nature makes them difficult to operationalize. Some organizations have therefore produced AI ethics checklists, as well as checklists for more specific concepts, such as fairness, as applied to AI systems. But unless checklists are grounded in practitioners' needs, they may be misused. To understand the role of checklists in AI ethics, we conducted an iterative co-design process with 48 practitioners, focusing on fairness. We co-designed an AI fairness checklist and identified desiderata and concerns for AI fairness checklists in general. We found that AI fairness checklists could provide organizational infrastructure for formalizing ad-hoc processes and empowering individual advocates. We highlight aspects of organizational culture that may impact the efficacy of AI fairness checklists, and suggest future design directions.

Recognizing Affiliation: Using Behavioural Traces to Predict the Quality of Social Interactions in Online Games

Online social interactions in multiplayer games can be supportive and positive or toxic and harmful; however, few methods can easily assess interpersonal interaction quality in games. We use behavioural traces to predict affiliation between dyadic strangers, facilitated through their social interactions in an online gaming setting. We collected audio, video, in-game, and self-report data from 23 dyads, extracted 75 features, trained Random Forest and Support Vector Machine models, and evaluated their performance predicting binary (high/low) as well as continuous affiliation toward a partner. The models can predict both binary and continuous affiliation with up to 79.1% accuracy (F1) and 20.1% explained variance (R2) on unseen data, with features based on verbal communication demonstrating the highest potential. Our findings can inform the design of multiplayer games and game communities, and guide the development of systems for matchmaking and mitigating toxic behaviour in online games.

Silva: Interactively Assessing Machine Learning Fairness Using Causality

Machine learning models risk encoding unfairness on the part of their developers or data sources. However, assessing fairness is challenging as analysts might misidentify sources of bias, fail to notice them, or misapply metrics. In this paper we introduce Silva, a system for exploring potential sources of unfairness in datasets or machine learning models interactively. Silva directs user attention to relationships between attributes through a global causal view, provides interactive recommendations, presents intermediate results, and visualizes metrics. We describe the implementation of Silva, identify salient design and technical challenges, and provide an evaluation of the tool in comparison to an existing fairness optimization tool.

Transparency of CHI Research Artifacts: Results of a Self-Reported Survey

Several fields of science are experiencing a "replication crisis" that has negatively impacted their credibility. Assessing the validity of a contribution via replicability of its experimental evidence and reproducibility of its analyses requires access to relevant study materials, data, and code. Failing to share them limits the ability to scrutinize or build-upon the research, ultimately hindering scientific progress.

Understanding how the diverse research artifacts in HCI impact sharing can help produce informed recommendations for individual researchers and policy-makers in HCI. Therefore, we surveyed authors of CHI 2018-2019 papers, asking if they share their papers' research materials and data, how they share them, and why they do not. The results (34% response rate) show that sharing is uncommon, partly due to misunderstandings about the purpose of sharing and reliable hosting. We conclude with recommendations for fostering open research practices.

This paper and all data and materials are freely available at

Quantification of Users' Visual Attention During Everyday Mobile Device Interactions

We present the first real-world dataset and quantitative evaluation of visual attention of mobile device users in-situ, i.e. while using their devices during everyday routine. Understanding user attention is a core research challenge in mobile HCI but previous approaches relied on usage logs or self-reports that are only proxies and consequently do neither reflect attention completely nor accurately. Our evaluations are based on Everyday Mobile Visual Attention (EMVA) – a new 32-participant dataset containing around 472 hours of video snippets recorded over more than two weeks in real life using the front-facing camera as well as associated usage logs, interaction events, and sensor data. Using an eye contact detection method, we are first to quantify the highly dynamic nature of everyday visual attention across users, mobile applications, and usage contexts. We discuss key insights from our analyses that highlight the potential and inform the design of future mobile attentive user interfaces.

Investigating User Expectations on the Roles of Family-shared AI Speakers

AI assistants that use a voice user interface (VUI), such as AI speakers, have become popular in family homes. However, it is still unclear what roles the AI speaker can support within the family unit. We investigated the roles of an AI speaker as a family-shared technology. By conducting a one-week participatory user study, we discovered that family members' co-ownership toward the AI speaker was the key in the development of its family-oriented roles. Our findings showed seven domains of user expectations on these roles, and we realized that all the expectations can be represented as family cohesion. In addition, privacy awareness was emphasized regarding personal supports. Finally, we discuss a new perspective for AI speaker design and offer two suggestions: 1) leveraging human-likeness to develop its potential roles of supporting the unit of a family and 2) interpreting the home context to seamlessly connect family and personal supporting roles.

Tempura: Query Analysis with Structural Templates

Analyzing queries from search engines and intelligent assistants is difficult. A key challenge is organizing queries into interpretable, context-preserving, representative, and flexible groups. We present structural templates, abstract queries that replace tokens with their linguistic feature forms, as a query grouping method. The templates allow analysts to create query groups with structural similarity at different granularities. We introduce Tempura, an interactive tool that lets analysts explore a query dataset with structural templates. Tempura summarizes a query dataset by selecting a representative subset of templates to show the query distribution. The tool also helps analysts navigate the template space by suggesting related templates likely to yield further explorations. Our user study shows that Tempura helps analysts examine the distribution of a query dataset, find labeling errors, and discover model error patterns and outliers.

C-Space: An Interactive Prototyping Platform for Collaborative Spatial Design Exploration

C-Space is an interactive prototyping platform for collaborative spatial design exploration. Spatial design projects often begin with conceptualization that includes abstract diagramming, zoning, and massing to provide a foundation for making design decisions. Specifically, abstract diagrams guide designers to explore alternative designs without thinking prematurely about the details. However, complications arise when communicating ambiguous and incomplete designs to collaborators. To overcome this drawback, designers devote considerable amounts of time and resources into searching for design references and creating rough prototypes to explicate their design concepts better. Therefore, this study proposes C-Space, a novel design support system that integrates the abstract diagram with design reference retrieval and prototyping through a tangible user interface and augmented reality. Through a user study with 12 spatial designers, we verify that C-Space promotes rapid and robust spatial design exploration, inducing collaborative discussions and motivating users to interact with designs.

Metaprobes, Metaphysical Workshops and Sketchy Philosophy

The intersection of philosophy and HCI is a longstanding site of interest for the field that has been attracting special attention in recent years. In this paper, we present metaphysical probes (Metaprobes) as a tool for design-led philosophical inquiry. A Metaprobe is a design artifact used to study a metaphysical idea without concealing the philosophical tools mobilized by the designers or the designerly knowledge attained after deployment. We introduce the concept of a Metaphysical Workshop. This is the set of sketchy philosophical notions that a designer mobilizes in order to research a philosophical idea through design. We then present a case study that comprises: the philosophical issue under examination, the Metaprobes designed to study it, the metaphysical workshop used and the designerly insight produced. We conclude with a discussion of the potentials and weaknesses of Metaprobes in relation to other critical and speculative research-through-design practices. We aim to provide one way to make philosophies already present in design more explicit and make other philosophical concepts relevant to HCI more accessible and workable for designers.

How Visualizing Inferential Uncertainty Can Mislead Readers About Treatment Effects in Scientific Results

When presenting visualizations of experimental results, scientists often choose to display either inferential uncertainty (e.g., uncertainty in the estimate of a population mean) or outcome uncertainty (e.g., variation of outcomes around that mean) about their estimates. How does this choice impact readers' beliefs about the size of treatment effects? We investigate this question in two experiments comparing 95% confidence intervals (means and standard errors) to 95% prediction intervals (means and standard deviations). The first experiment finds that participants are willing to pay more for and overestimate the effect of a treatment when shown confidence intervals relative to prediction intervals. The second experiment evaluates how alternative visualizations compare to standard visualizations for different effect sizes. We find that axis rescaling reduces error, but not as well as prediction intervals or animated hypothetical outcome plots (HOPs), and that depicting inferential uncertainty causes participants to underestimate variability in individual outcomes.

Integrated Development Environment with Interactive Scatter Plot for Examining Statistical Modeling

The development of a statistical modeling program requires example data to observe and verify the behavior of the program. Such example data are either taken from an existing dataset or synthesized using commands. Programmers may want to directly design an arbitrary dataset or modify it interactively, but it is difficult to do so in current development environments. We therefore propose combining a code editor with an interactive scatter plot editor to efficiently understand the behavior of statistical modeling algorithms. The user interactively creates and modifies the dataset on the scatter plot editor, while the system continuously executes the code in the editor, taking the data as input, and shows the result in the editor. This paper presents the design rationale behind the system and introduces several usage scenarios.

Many Faced Hate: A Cross Platform Study of Content Framing and Information Sharing by Online Hate Groups

Hate groups are increasingly using multiple social media platforms to promote extremist ideologies. Yet we know little about their communication practices across platforms. How do hate groups (or "in-groups"), frame their hateful agenda against the targeted group or the "out-group?" How do they share information? Utilizing "framing" theory from social movement research and analyzing domains in the shared links, we juxtapose the Facebook and Twitter communication of 72 Southern Poverty Law Center (SPLC) designated hate groups spanning five hate ideologies. Our findings show that hate groups use Twitter for educating the audience about problems with the out-group, maintaining positive self-image by emphasizing in-group's high social status, and for demanding policy changes to negatively affect the out-group. On Facebook, they use fear appeals, call for active participation in group events (membership requests), all while portraying themselves as being oppressed by the out-group and failed by the system. Our study unravels the ecosystem of cross-platform communication by hate groups, suggesting that they use Facebook for group radicalization and recruitment, while Twitter for reaching a diverse follower base.

How Mandatory Second Factor Affects the Authentication User Experience

Recent years have seen growing organizational adoption of two-factor authentication as organizations seek to limit the damage caused by password breaches. However, research on the user experience of two-factor authentication in a real-world setting is relatively scant. To fill this gap, we conducted multiple waves of an online survey of users at a large public university during its multi-phase rollout of mandatory two-factor authentication for faculty, staff, and students. In addition, we examined multiple months of logs of all authentication events at the university. We found no significant changes in user experience and acceptance of two-factor authentication when it was mandatory for select systems that dealt with sensitive information. However, these factors degraded when users were forced to use two-factor authentication for logging into every single university resource. Our findings can serve as important guidance for the implementation of two-factor authentication in organizations in a way that can help achieve a balance between security and user experience.

Supporting the Supporters of Unaccompanied Migrant Youth: Designing for Social-ecological Resilience

Unaccompanied migrant youth, fleeing to a new country without their parents, are exposed to mental health risks. Resilience interventions mitigate such risks, but access can be hindered by systemic and personal barriers. While much work has recently addressed designing technology to promote mental health, none has focused on the needs of these populations. This paper presents the results of interviews with 18 professional/ volunteer support workers and 5 unaccompanied migrant youths, followed by three design workshops. The results point to the diverse systems that can facilitate youths' resilience development. The relationship between the youth and volunteers acting as mentors is particularly important for increasing resilience but comes with challenges. This suggests the relevance of a social-ecological model of resilience with a focus on designing technology to support the mentors in order to help them better support the youth. We conclude by mapping out the design space for mentor support.

Dimensions of UX Practice that Shape Ethical Awareness

HCI researchers are increasingly interested in describing the complexity of design practice, including ethical, organizational, and societal concerns. Recent studies have identified individual practitioners as key actors in driving the design process and culture within their respective organizations, and we build upon these efforts to reveal practitioner concerns regarding ethics on their own terms. In this paper, we report on the results of an interview study with eleven UX practitioners, capturing their experiences that highlight dimensions of design practice that impact ethical awareness and action. Using a bottom-up thematic analysis, we identified five dimensions of design complexity that influence ethical outcomes and span individual, collaborative, and methodological framing of UX activity. Based on these findings, we propose a set of implications for the creation of ethically-centered design methods that resonate with this complexity and inform the education of future UX practitioners.

Storytelling to Sensemaking: A Systematic Framework for Designing Auditory Description Display for Interactives

Auditory description display is verbalized text typically used to describe live, recorded, or graphical displays to support access for people who are blind or visually impaired. Significant prior research has resulted in guidelines for auditory description for non-interactive or minimally interactive contexts. A lack of auditory description for complex interactive environments remains a tremendous barrier to access for people with visual impairments. In this work, we present a systematic design framework for designing auditory description within complex interactive environments. We illustrate how modular descriptions aligned with this framework can result in an interactive storytelling experience constructed through user interactions. This framework has been used in a set of published and widely used interactive science simulations, and in its generalized form could be applied to a variety of contexts.

Empathy Is All You Need: How a Conversational Agent Should Respond to Verbal Abuse

With the popularity of AI-infused systems, conversational agents (CAs) are becoming essential in diverse areas, offering new functionality and convenience, but simultaneously, suffering misuse and verbal abuse. We examine whether conversational agents' response styles under varying abuse types influence those emotions found to mitigate peoples' aggressive behaviors, involving three verbal abuse types (Insult, Threat, Swearing) and three response styles (Avoidance, Empathy, Counterattacking). Ninety-eight participants were assigned to one of the abuse type conditions, interacted with the three spoken (voice-based) CAs in turn, and reported their feelings about guiltiness, anger, and shame after each session. The results show that the agent's response style has a significant effect on user emotions. Participants were less angry and more guilty with the empathy agent than the other two agents. Furthermore, we investigated the current status of commercial CAs' responses to verbal abuse. Our study findings have direct implications for the design of conversational agents.

Brooke Leave Home: Designing a Personalized Film to Support Public Engagement with Open Data

Brooke Leave Home is a personalized film designed to engage a non-expert audience with open data about the support young adults receive when leaving the care system in England. The film draws upon a range of video-based data storytelling techniques to present each viewer with a personalized perspective on the topic based on data from their own local area. We present the film's design and describe how its storytelling techniques were developed to support viewers in understanding, and fostering empathic connections with, the data sources featured and the implications they have for care leavers. We also present a study with 47 viewers, which explores how these techniques were experienced and how effective they were in aiding engagement with the data included and its meaning.

Automation and Creativity: A Case Study of DJs' and VJs' Ambivalent Positions on Automated Visual Software

Computerized solutions in the domain of creativity and expressive performance increasingly provide art and artists with exciting new opportunities. However, the combination of automation and creativity also raises controversies and resistance in some user groups. This paper considers the case of software-generated visuals in live music performance and tries to make sense of the ambivalent response given by its intended users (i.e., DJs and VJs). We carried out seven face-to-face interviews, an online survey (N = 102) and 25 interviews at a distance to unravel DJs' and VJs' positions on automated visual software. Four core controversies were eventually identified, gravitating around the implications of using such software on DJs' and VJs' identities as artists and on their competitive advantage in their activity sector. The conclusions reconnect these findings with the larger issue of understanding the users' responses to automation.

From Creating Spaces for Civic Discourse to Creating Resources for Action

In this paper, we investigate the role of technology to address the concerns of a civil society group carrying out community-level consultation on the allocation of £1 million of community funds. We explore issues of devolved decision-making through the evaluation of a sociodigital system designed to foster deliberative virtues. We describe the ways in which this group used our system in their consultation practices. Our findings highlight how they adopted our technology to privilege specific forms of expression, ascertain issues in their community, make use of and make sense of community data, and create resources for action within their existing practices. Based on related fieldwork we discuss the impacts of structuring and configuring tools for 'talk-based' consultation in order to turn attention to the potential pitfalls and prospects for designing civic technologies that create resources for action for civil society.

"Like Shock Absorbers": Understanding the Human Infrastructures of Technology-Mediated Mental Health Support

Significant research in HCI and beyond has sought to understand end-user needs in formal and informal technology-mediated mental health support (TMMHS) systems. However, little work has been done to understand the experiences and needs of the individuals who power or support these systems, particularly in the Global South. We present a qualitative study of one of the most accessible forms of mental health care in India — helplines. Through in-depth interviews conducted with 12 helpline volunteers, we research the human infrastructure responsible for the functioning of helplines. We foreground the often invisible labor involved in erecting and maintaining the institutional, interpersonal, and individual boundaries that are critical to realizing the goals of these helplines. Finally, we discuss the implications of our research for future work examining human infrastructures, particularly in mental health settings, and for the design of future TMMHS systems that deliver on-demand care to diverse, underserved, and stigmatized populations.

A Probabilistic Grammar of Graphics

Visualizations depicting probabilities and uncertainty are used everywhere from medical risk communication to machine learning, yet these probabilistic visualizations are difficult to specify, prone to error, and their designs are cumbersome to explore. We propose a Probabilistic Grammar of Graphics (PGoG), an extension to Wilkinson's original framework. Inspired by the success of probabilistic programming languages, PGoG makes probability expressions, such as P(A|B), a first-class citizen in the language. PGoG abstractions also reflect the distinction between probability and frequency framing, a concept from the uncertainty communication literature. It is expressive, encompassing product plots, density plots, icon arrays, and dotplots, among other visualizations. Its coherent syntax ensures correctness (that the proportions of visual elements and their spatial placement reflect the underlying probability distribution) and reduces edit distance between probabilistic visualization specifications, potentially supporting more design exploration. We provide a proof-of-concept implementation of PGoG in R.

Answering Questions about Charts and Generating Visual Explanations

People often use charts to analyze data, answer questions and explain their answers to others. In a formative study, we find that such human-generated questions and explanations commonly refer to visual features of charts. Based on this study, we developed an automatic chart question answering pipeline that generates visual explanations describing how the answer was obtained. Our pipeline first extracts the data and visual encodings from an input Vega-Lite chart. Then, given a natural language question about the chart, it transforms references to visual attributes into references to the data. It next applies a state-of-the-art machine learning algorithm to answer the transformed question. Finally, it uses a template-based approach to explain in natural language how the answer is determined from the chart's visual features. A user study finds that our pipeline-generated visual explanations significantly outperform in transparency and are comparable in usefulness and trust to human-generated explanations.

Adults' and Children's Mental Models for Gestural Interactions with Interactive Spherical Displays

Interactive spherical displays offer numerous opportunities for engagement and education in public settings. Prior work established that users' touch-gesture patterns on spherical displays differ from those on flatscreen tabletops, and speculated that these differences stem from dissimilarity in how users conceptualize interactions with these two form factors. We analyzed think-aloud data collected during a gesture elicitation study to understand adults' and children's (ages 7 to 11) conceptual models of interaction with spherical displays and compared them to conceptual models of interaction with tabletop displays from prior work. Our findings confirm that the form factor strongly influenced users' mental models of interaction with the sphere. For example, participants conceptualized that the spherical display would respond to gestures in a similar way as real-world spherical objects like physical globes. Our work contributes new understanding of how users draw upon the perceived affordances of the sphere as well as prior touchscreen experience during their interactions.

Towards Value-Adaptive Instruction: A Data-Driven Method for Addressing Bias in Argument Evaluation Tasks

As the media landscape is increasingly populated by less than reputable sources of information, educators have turned to argument evaluation training as a potential solution. Unfortunately, the bias literature suggests that our ability to objectively evaluate an argument is, to a large extent, determined by the relationship between our own beliefs and the beliefs latent in the argument we are evaluating. If the argument supports our worldview, we are much more likely to overlook logical errors. Teachers recognize this need to adapt argument evaluation instruction to the specific beliefs of students. For instance, a teacher might intentionally assign a student an argument that the student disagrees with. Unfortunately, this kind of value-adaptive instruction is infrequent due to its unscalability. We propose a novel method for data-driven value-adaptive instruction in instructional technologies. This method can be used to combat bias in real-world contexts and support human reasoning during media consumption.

Wireality: Enabling Complex Tangible Geometries in Virtual Reality with Worn Multi-String Haptics

Today's virtual reality (VR) systems allow users to explore immersive new worlds and experiences through sight. Unfortunately, most VR systems lack haptic feedback, and even high-end consumer systems use only basic vibration motors. This clearly precludes realistic physical interactions with virtual objects. Larger obstacles, such as walls, railings, and furniture are not simulated at all. In response, we developed Wireality, a self-contained worn system that allows for individual joints on the hands to be accurately arrested in 3D space through the use of retractable wires that can be programmatically locked. This allows for convincing tangible interactions with complex geometries, such as wrapping fingers around a railing. Our approach is lightweight, low-cost, and low-power, criteria important for future, worn consumer uses. In our studies, we further show that our system is fast-acting, spatially-accurate, high-strength, comfortable, and immersive.

Touching and Being in Touch with the Menstruating Body

We describe a Research through Design project-Curious Cycles-a collection of objects and interactions which encourage people to be in close contact with their menstruating body. Throughout a full menstrual cycle, five participants used Curious Cycles to look at their bodies in unfamiliar ways and to touch their bodily fluids, specifically, menstrual blood, saliva, and cervical mucus. The act of touching and looking led to the construction of new knowledge about the self and to a nurturing appreciation for the changing body. Yet, participants encountered and reflected upon frictions within themselves, their home, and their social surroundings, which stem from societal stigma and preconceptions about menstruation and bodily fluids. We call for and show how interaction design can engage with technologies that mediate self-touch as a first step towards reconfiguring the way menstruating bodies are treated in society.

Towards Inclusive External Communication of Autonomous Vehicles for Pedestrians with Vision Impairments

People with vision impairments (VIP) are among the most vulnerable road users in traffic. Autonomous vehicles are believed to reduce accidents but still demand some form of external communication signaling relevant information to pedestrians. Recent research on the design of vehicle-pedestrian communication (VPC) focuses strongly on concepts for a non-disabled population. Our work presents an inclusive user-centered design for VPC, beneficial for both vision impaired and seeing pedestrians. We conducted a workshop with VIP (N=6), discussing current issues in road traffic and comparing communication concepts proposed by literature. A thematic analysis unveiled two important themes: number of communicating vehicles and content (affecting duration). Subsequently, we investigated these in a second user study in virtual reality (N=33, 8 VIP) comparing the VPC between groups of abilities. We found that trust and understanding is enhanced and cognitive load reduced when all relevant vehicles communicate; high content messages also reduce cognitive load.

Crowdsourcing in China: Exploring the Work Experiences of Solo Crowdworkers and Crowdfarm Workers

Recent research highlights the potential of crowdsourcing in China. Yet very few studies explore the workplace context and experiences of Chinese crowdworkers. Those that do, focus mainly on the work experiences of solo crowdworkers but do not deal with issues pertaining to the substantial amount of people working in 'crowdfarms'. This article addresses this gap as one of its primary concerns. Drawing on a study that involves 48 participants, our research explores, compares and contrasts the work experiences of solo crowdworkers to those of crowdfarm workers. Our findings illustrate that the work experiences and context of the solo workers and crowdfarm workers are substantially different, with regards to their motivations, the ways they engage with crowdsourcing, the tasks they work on, and the crowdsourcing platforms they utilize. Overall, our study contributes to furthering the understandings on the work experiences of crowdworkers in China.

Co-designing Digital Tools to Enhance Speech and Language Therapy Training in Ghana

Ghana has a population of over 27 million people, of which 1 in 15 may have a communication disability. The number of speech and language therapists (SLTs) available to support these people remains remarkably small, presenting a major workforce challenge. As an emerging profession, there remain significant challenges around educating the first generation of SLTs. Ghana, however, has a healthy digital infrastructure which can be taken advantage of. We describe a comprehensive study which aimed to co-design a set of locally appropriate digital tools to enhance SLT training in Ghana. We contribute insights into how digital tools could support social learning and the transition from student to independent practitioner and future clinical supervisor. We offer a set of design recommendations for creating an online Community of Practice to enhance continuing professional development.

Toward Future-Centric Personal Informatics: Expecting Stressful Events and Preparing Personalized Interventions in Stress Management

Stress is caused by a variety of events in our daily lives. By anticipating stressful situations, we can prepare and better cope with stressors when they actually occur. However, many past-centric personal informatics (PI) tools focus on capturing events that already happened and analyzing the data. In this work, we examine how anticipation — a future-centric self-tracking practice — could be used to manage daily stress levels. To address this, we built MindForecaster, a calendar- mediated stress anticipation application that allows users to expect stressful events in advance, generates activities to mitigate stress, and evaluates actual stress levels compared to previously estimated stress levels. In a 30-day deployment with 47 users, the users who explicitly planned and executed coping interventions reported reduced stress more than those who only expected stressful events. We suggest design implications for stress management by incorporating the properties of anticipation into current PI models.

Haptic-go-round: A Surrounding Platform for Encounter-type Haptics in Virtual Reality Experiences

We present Haptic-go-round, a surrounding platform that allows deploying props and devices to provide haptic feedbacks in any direction in virtual reality experiences. The key component of Haptic-go-round is a motorized turntable that rotates the correct haptic device to the right direction at the right time to match what users are about to touch. We implemented a working platform including plug-and-play prop cartridges and a software interface that allow experience designers to agilely add their haptic components and use the platform for their applications. We conducted technical experiments and two user studies on Haptic-go-round to evaluate its performance. We report the results and discuss our insights and limitations.

Weaving by Touch: A Case Analysis of Accessible Making

The rise of maker communities and fabrication tools creates new opportunities for participation in design work. With this has come an interest in increasing the accessibility of making for people with disabilities, which has mainly emphasized independence and empowerment through the creation of more accessible fabrication tools. To understand and rethink the notion of accessible making, we analyze the context and practices of a particular site of making: the communal weaving studio within an assisted living facility for people with vision impairments. Our analysis helps reconsider the material and social processes that constitute accessible making, including the ways makers attend to interactive material properties, negotiate co-creative embodied work, and value the labor of making. We discuss future directions for design and research on accessible making while highlighting tensions around assistance, collaboration, and how disabled labor is valued.

Designing Ambient Narrative-Based Interfaces to Reflect and Motivate Physical Activity

Numerous technologies now exist for promoting more active lifestyles. However, while quantitative data representations (e.g., charts, graphs, and statistical reports) typify most health tools, growing evidence suggests such feedback can not only fail to motivate behavior but may also harm self-integrity and fuel negative mindsets about exercise. Our research seeks to devise alternative, more qualitative schemes for encoding personal information. In particular, this paper explores the design of data-driven narratives, given the intuitive and persuasive power of stories. We present WhoIsZuki, a smartphone application that visualizes physical activities and goals as components of a multi-chapter quest, where the main character's progress is tied to the user's. We report on our design process involving online surveys, in-lab studies, and in-the-wild deployments, aimed at refining the interface and the narrative and gaining a deep understanding of people's experiences with this type of feedback. From these insights, we contribute recommendations to guide future development of narrative-based applications for motivating healthy behavior.

Enhancing Mobile Voice Assistants with WorldGaze

Contemporary voice assistants require that objects of inter-est be specified in spoken commands. Of course, users are often looking directly at the object or place of interest ? fine-grained, contextual information that is currently unused. We present WorldGaze, a software-only method for smartphones that provides the real-world gaze location of a user that voice agents can utilize for rapid, natural, and precise interactions. We achieve this by simultaneously opening the front and rear cameras of a smartphone. The front-facing camera is used to track the head in 3D, including estimating its direction vector. As the geometry of the front and back cameras are fixed and known, we can raycast the head vector into the 3D world scene as captured by the rear-facing camera. This allows the user to intuitively define an object or region of interest using their head gaze. We started our investigations with a qualitative exploration of competing methods, before developing a functional, real-time implementation. We conclude with an evaluation that shows WorldGaze can be quick and accurate, opening new multimodal gaze+voice interactions for mobile voice agents.

Toward the Design of Enjoyable Games for Children with Fetal Alcohol Spectrum Disorder

Fetal Alcohol Spectrum Disorder (FASD) is a heterogeneous and complex set of disorders caused by prenatal alcohol exposure, estimated to affect 2-5% of the North American population. Deficits associated with FASD affect social skill development and executive function, including emotional regulation and impulse control. These deficits can increase the difficulty of playing digital games. While considerable research has been performed in understanding how to design games for people with neurodevelopmental disorders in general, there is little data on how to design engaging games for children with FASD. We conducted a ten-week in-school gaming trial with eleven elementary-aged children with diagnosed or suspected FASD. Participants enjoyed playing together and responded well to the in-game reward system, while some game elements caused unexpected frustration. Based on our observations, we advise that games for FASD be designed to have low cost of failure, avoid retracting options, account for taking breaks when needed, show progression in rewards, and enable cooperative play.

FaceHaptics: Robot Arm based Versatile Facial Haptics for Immersive Environments

This paper introduces FaceHaptics, a novel haptic display based on a robot arm attached to a head-mounted virtual reality display. It provides localized, multi-directional and movable haptic cues in the form of wind, warmth, moving and single-point touch events and water spray to dedicated parts of the face not covered by the head-mounted display.The easily extensible system, however, can principally mount any type of compact haptic actuator or object. User study 1 showed that users appreciate the directional resolution of cues, and can judge wind direction well, especially when they move their head and wind direction is adjusted dynamically to compensate for head rotations. Study 2 showed that adding FaceHaptics cues to a VR walkthrough can significantly improve user experience, presence, and emotional responses.

Social Comparison and Facebook: Feedback, Positivity, and Opportunities for Comparison

People compare themselves to one another both offline and online. The specific online activities that worsen social comparison are partly understood, though much existing research relies on people recalling their own online activities post hoc and is situated in only a few countries. To better understand social comparison worldwide and the range of associated behaviors on social media, a survey of 38,000 people from 18 countries was paired with logged activity on Facebook for the prior month. People who reported more frequent social comparison spent more time on Facebook, had more friends, and saw proportionally more social content on the site. They also saw greater amounts of feedback on friends' posts and proportionally more positivity. There was no evidence that social comparison happened more with acquaintances than close friends. One in five respondents recalled recently seeing a post that made them feel worse about themselves but reported conflicting views: half wished they hadn't seen the post, while a third felt very happy for the poster. Design opportunities are discussed, including hiding feedback counts, filters for topics and people, and supporting meaningful interactions, so that when comparisons do occur, people are less affected by them.

KeyMap: Improving Keyboard Shortcut Vocabulary Using Norman's Mapping

We introduce a new shortcut interface called KeyMap that is designed to leverage Norman's principle of natural mapping. Rather than displaying shortcut command labels in linear menus, KeyMap displays a virtual keyboard with command labels displayed directly on its keys. A crowdsourced experiment compares KeyMap to Malacria et al.'s ExposeHK using an extension of their protocol to also test recall. Results show KeyMap users remembered 1 more shortcut than ExposeHK immediately after training, and this advantage increased to 4.5 more shortcuts when tested again after 24 hours. KeyMap users also incidentally learned more shortcuts that they had never practised. We demonstrate how KeyMap can be added to existing web-based applications using a Chrome extension.

A Longitudinal Video Study on Communicating Status and Intent for Self-Driving Vehicle – Pedestrian Interaction

With self-driving vehicles (SDVs), pedestrians cannot rely on communication with the driver anymore. Industry experts and policymakers are proposing an external Human-Machine Interface (eHMI) communicating the automated status. We investigated whether additionally communicating SDVs' intent to give right of way further improves pedestrians' street crossing. To evaluate the stability of these eHMI effects, we conducted a three-session video study with N=34 pedestrians where we assessed subjective evaluations and crossing onset times. This is the first work capturing long-term effects of eHMIs. Our findings add credibility to prior studies by showing that eHMI effects last (acceptance, user experience) or even increase (crossing onset, perceived safety, trust, learnability, reliance) with time. We found that pedestrians benefit from an eHMI communicating SDVs' status, and that additionally communicating SDVs' intent adds further value. We conclude that SDVs should be equipped with an eHMI communicating both status and intent.

Debugging Database Queries: A Survey of Tools, Techniques, and Users

Database management systems (or DBMSs) have been around for decades, and yet are still difficult to use, particularly when trying to identify and fix errors in user programs (or queries). We seek to understand what methods have been proposed to help people debug database queries, and whether these techniques have ultimately been adopted by DBMSs (and users). We conducted an interdisciplinary review of 112 papers and tools from the database, visualisation and HCI communities. To better understand whether academic and industry approaches are meeting the needs of users, we interviewed 20 database users (and some designers), and found surprising results. In particular, there seems to be a wide gulf between users' debugging strategies and the functionality implemented in existing DBMSs, as well as proposed in the literature. In response, we propose new design guidelines to help system designers to build features that more closely match users debugging strategies.

FamilyStories: Asynchronous Audio Storytelling for Family Members Across Time Zones

Family members who are separated across time zones can easily miss out on feeling connected. We designed and studied the usage of an asynchronous storytelling system, called FamilyStories, to explore the use of audio-based sharing. FamilyStories allows family members to share activities and experiences over distance in different time zones using three different devices that contain different contextual features. To evaluate the design, we conducted a five-week long field study with two family member pairs. Our results show the value of slow, flexible, and non-suggestive interfaces for asynchronous audio communication. We also found ephemerality helped in the sharing of 'instant' feelings, while large time zone differences could be 'synchronized' with time delayed messages. We raise these as design opportunities for asynchronous audio storytelling systems.

Detecting Gender Stereotypes: Lexicon vs. Supervised Learning Methods

Biases in language influence how we interact with each other and society at large. Language affirming gender stereotypes is often observed in various contexts today, from recommendation letters and Wikipedia entries to fiction novels and movie dialogue. Yet to date, there is little agreement on the methodology to quantify gender stereotypes in natural language (specifically the English language). Common methodology (including those adopted by companies tasked with detecting gender bias) rely on a lexicon approach largely based on the original BSRI study from 1974.

In this paper, we reexamine the role of gender stereotype detection in the context of modern tools, by comparatively analyzing efficacy of lexicon-based approaches and end-to-end, ML-based approaches prevalent in state-of-the-art natural language processing systems. Our efforts using a large dataset show that even compared to an updated lexicon-based approach, end-to-end classification approaches are significantly more robust and accurate, even when trained by moderately sized corpora.

Head-Coupled Kinematic Template Matching: A Prediction Model for Ray Pointing in VR

This paper presents a new technique to predict the ray pointer landing position for selection movements in virtual reality (VR) environments. The technique adapts and extends a prior 2D kinematic template matching method to VR environments where ray pointers are used for selection. It builds on the insight that the kinematics of a controller and Head-Mounted Display (HMD) can be used to predict the ray's final landing position and angle. An initial study provides evidence that the motion of the head is a key input channel for improving prediction models. A second study validates this technique across a continuous range of distances, angles, and target sizes. On average, the technique's predictions were within 7.3° of the true landing position when 50% of the way through the movement and within 3.4° when 90%. Furthermore, compared to a direct extension of Kinematic Template Matching, which only uses controller movement, this head-coupled approach increases prediction accuracy by a factor of 1.8x when 40% of the way through the movement.

CreaTable Content and Tangible Interaction in Aphasia

Multimedia digital content (combining pictures, text and music) is ubiquitous. The process of creating such content using existing tools typically requires complex, language-laden interactions which pose a challenge for users with aphasia (a language impairment following brain injury). Tangible interactions offer a potential means to address this challenge, however, there has been little work exploring their potential for this purpose. In this paper, we present CreaTable a platform that enables us to explore tangible interaction as a means of supporting digital content creation for people with aphasia. We report details of the co-design of CreaTable and findings from a digital creativity workshop. Workshop findings indicated that CreaTable enabled people with aphasia to create something they would not otherwise have been able to. We report how users' aphasia profiles affected their experience, describe tensions in collaborative content creation and provide insight into more accessible content creation using tangibles.

Touch me Gently: Recreating the Perception of Touch using a Shape-Memory Alloy Matrix

We present a wearable forearm augmentation that enables the recreation of natural touch sensation by applying shear-forces onto the skin. In contrast to previous approaches, we arrange light-weight and stretchable 3x3cm plasters in a matrix onto the skin. Individual plasters were embedded with lines of shape-memory alloy (SMA) wires to generate shear-forces. Our design is informed by a series of studies investigating the perceptibility of different sizes, spacings, and attachments of plasters on the forearm. Our matrix arrangement enables the perception of touches, for instance, feeling ones wrist being grabbed or the arm being stroked. Users rated the recreated touch sensations as being fairly similar to a real touch (4.1/5). Even without a visual representation, users were able to correctly distinguish them with an overall accuracy of 94.75%. Finally, we explored two use cases showing how AR and VR could be empowered with experiencing recreated touch sensations on the forearm.

Designing for Social Interaction in the Age of Excessive Smartphone Use

Excessive smartphone use has negative effects on our social relations as well as on our mental and psychological health. Most of the previous work to avoid these negative effects is based on a top-down approach such as restricting or limiting users' use of smartphones. Diverging from previous work, we followed a bottom-up approach to understand the practice of smartphone use in public settings from the users' perspective. We conducted observations in four coffeehouses, six focus group sessions with 46 participants and three design workshops with 15 designers. We identified five themes that help better understand smartphone use behavior in public settings and four alternative design approaches to mediate this behavior, namely enlighteners, preventers, supporters, and compliers. We discuss the implications of these themes and approaches for designing future interactive technologies aimed at mediating excessive smartphone use behavior.

Giving Voice to Silent Data: Designing with Personal Music Listening History

Music streaming services collect listener data to support personalization and discovery of their extensive catalogs. Yet this data is typically used in ways that are not immediately apparent to listeners. We conducted design workshops with ten Spotify listeners to imagine future voice assistant (VA) interactions leveraging logged music data. We provided participants with detailed personal music listening data, such as play-counts and temporal patterns, which grounded their design ideas in their current behaviors. In the interactions participants designed, VAs did not simply speak their data out loud; instead, participants envisioned how data could implicitly support introspection, behavior change, and exploration. We present reflections on how VAs could evolve from voice-activated remote controls to intelligent music coaches and how personal data can be leveraged as a design resource.

Projection Boxes: On-the-fly Reconfigurable Visualization for Live Programming

Live programming is a regime in which the programming environment provides continual feedback, most often in the form of runtime values. In this paper, we present Projection Boxes, a novel visualization technique for displaying runtime values of programs. The key idea behind projection boxes is to start with a full semantics of the program, and then use projections to pick a subset of the semantics to display. By varying the projection used, projection boxes can encode both previously known visualization techniques, and also new ones. As such, projection boxes provide an expressive and configurable framework for displaying runtime information. Through a user study we demonstrate that (1) users find projection boxes and their configurability useful (2) users are not distracted by the always-on visualization (3) a key driving force behind the need for a configurable visualization for live programming lies with the wide variation in programmer preferences.

When Design Novices and LEGO® Meet: Stimulating Creative Thinking for Interface Design

Design thinking is an iterative, human-centered approach to innovation. Its success rests on collaboration within a multidisciplinary project team going through cycles of divergent and convergent ideations. In these teams, nondesigners risk diminishing the divergent reach because they are generally reluctant to sketch, thus missing out on theambiguous, imprecise early conceptual divergent phases. We hypothesized that LEGO® could advantageously be a substitute to sketching. In this comparative study, 44 nondesigners randomly paired in 22 dyads did two conceptual ideations of healthcare landing pages, one using pen/paper (spontaneously writing words on sticky notes) and the other using LEGO, assessed through Torrance and Guilford frameworks for divergent thinking. Results show that LEGO interfaces gathered significantly higher divergent thinking scores because their concepts were significantly more elaborated. Furthermore, when using LEGO, teams who generated more elements were likely to also generate more ideas, more categories of ideas and more original ideas.

Framing Effects Influence Interface Feature Decisions

Studies in psychology have shown that framing effects, where the positive or negative attributes of logically equivalent choices are emphasised, influence people's decisions. When outcomes are uncertain, framing effects also induce patterns of choice reversal, where decisions tend to be risk averse when gains are emphasised and risk seeking when losses are emphasised. Studies of these effects typically use potent framing stimuli, such as the mortality of people suffering from diseases or personal financial standing. We examine whether these effects arise in users' decisions about interface features, which typically have less visceral consequences, using a crowd-sourced study based on snap-to-grid drag-and-drop tasks (n = 842). The study examined several framing conditions: those similar to prior psychological research, and those similar to typical interaction choices (enabling/disabling features). Results indicate that attribute framing strongly influences users' decisions, that these decisions conform to patterns of risk seeking for losses, and that patterns of choice reversal occur.

"'More gay' fits in better": Intracommunity Power Dynamics and Harms in Online LGBTQ+ Spaces

Online spaces play crucial roles in the lives of most LGBTQ+ people, but can also replicate and exacerbate existing intracommunity tensions and power dynamics, potentially harming subgroups within this marginalized community. Using qualitative probes and interviews, we engaged a diverse group of 25 bi+ (attracted to more than one gender) people to explore these dynamics. We identify two types of intracommunity conflict that bi+ users face (validity and normative conflicts), and a resulting set of what we call latent harms, or coping strategies for dealing with conflict that have delayed negative psychological effects for bi+ users. Using intersectionality as a sensitizing concept to understand shifting power dynamics embedded in sociotechnical contexts, we discuss challenges for future design work including the need to account for intracommunity dynamics within marginalized groups and the utility of disentangling conflict from harm.

Towards A Taxonomy of Content Sensitivity and Sharing Preferences for Photos

Determining which photos are sensitive is difficult. Although emerging computer vision systems can label content items, previous attempts to distinguish private or sensitive content fall short. There is no human-centered taxonomy that describes what content is sensitive or how sharing preferences for content differs across recipients. To fill this gap, we introduce a new sensitive content elicitation method which surmounts limitations of previous approaches, and, using this new method, collected sensitive content from 116 participants. We also recorded participants' sharing preferences with 20 recipient groups. Next, we conducted a card sort to surface user-defined categories of sensitive content. Using data from these studies, we generated a taxonomy that identifies 28 categories of sensitive content. We also establish how sharing preferences for content differs across groups of recipients. This taxonomy can serve as a framework for understanding photo privacy, which can, in turn, inform new photo privacy protection mechanisms.

E-scooters on the Ground: Lessons for Redesigning Urban Micro-Mobility

The worldwide deployment of rental electric scooters has generated new opportunities for urban mobility, but also intensified conflict over public space. This article reports on an ethnographic study of both rental and privately-owned e-scooters, mapping out the main problems and potentials around this new form of 'micro-mobility'. While it suffers from problems of reliability and conflict, user experience is an important part of e-scooters' appeal, an enjoyable way of 'hacking the city'. E-scooters have a hybrid character: weaving through the city, riders can switch between riding as a pedestrian, a car or a bicycle. Building on these results, we discuss how e-scooters, ridesharing services, and their apps could develop further, alongside the role for HCI in re-thinking urban transport and vehicle design.

GridAlert: Using a Sensor-Based Technology to Monitor Power Blackouts in Kenyan Homes

Power blackouts (outages) are a common occurrence in Kenyan households. They affect people's livelihoods, and damage their property (household electrical items). We explore the role of GridAlert-a sensor-based technology we designed-in monitoring power blackouts. We worked with local technicians to design GridAlert's housing and integrate GridAlert with Kenya's electricity infrastructure. Then, we used interview, observation, diary, and data logging methods to understand 18 households' experiences using the system. Our findings provide insights for using sensor-based technology to monitor power usage and blackouts in Kenyan households. We also present participants' thoughts about GridAlert's housing, and about how it influenced their actions when using the system. We use these findings to discuss design insights for power monitoring systems, and to offer new perspectives on the role of technology in monitoring blackouts in Kenyan households.

Exploring the Design Space of User-System Communication for Smart-home Routine Assistants

AI-enabled smart-home agents that automate household routines are increasingly viable, but the design space of how and what such systems should communicate with their users remains underexplored. Through a user-enactment study, we identified various interpretations of and feelings toward such a system's confidence in its automated acts. That confidence and their own mental models influenced what and how the participants wanted the system to communicate, as well as how they would assess, diagnose, and subsequently improve it. Automated acts resulted from false predictions were not generally considered improper, provided that they were perceived as reasonable or potentially useful. The participants' improvement strategies were of four general types, all of which will be discussed. Factors affecting their preferred levels of involvement in automated acts and their interest in system confidence were also identified. We conclude by making practical design recommendations for the user-system communication design spaces of smart-home routine assistants.

A Literature Review of Quantitative Persona Creation

Quantitative persona creation (QPC) has tremendous potential, as HCI researchers and practitioners can leverage user data from online analytics and digital media platforms to better understand their users and customers. However, there is a lack of a systematic overview of the QPC methods and progress made, with no standard methodology or known best practices. To address this gap, we review 49 QPC research articles from 2005 to 2019. Results indicate three stages of QPC research: Emergence, Diversification, and Sophistication. Sharing resources, such as datasets, code, and algorithms, is crucial to achieving the next stage (Maturity). For practitioners, we provide guiding questions for assessing QPC readiness in organizations.

Digital Ventriloquism: Giving Voice to Everyday Objects

Smart speakers with voice agents are becoming increasingly common. However, the agent's voice always emanates from the device, even when that information is contextually and spatially relevant elsewhere. Digital Ventriloquism allows smart speakers to render sound onto everyday objects, such that it appears they are speaking and are interactive. This can be achieved without any modification of objects or the environment. For this, we used a highly directional pan-tilt ultrasonic array. By modulating a 40 kHz ultrasonic signal, we can emit sound that is inaudible "in flight" and demodulates to audible frequencies when impacting a surface through acoustic parametric interaction. This makes it appear as though the sound originates from an object and not the speaker. We ran a study in which we projected speech onto five objects in three environments, and found that participants were able to correctly identify the source object 92% of the time and correctly repeat the spoken message 100% of the time, demonstrating our digital ventriloquy is both directional and intelligible.

Affective State Prediction Based on Semi-Supervised Learning from Smartphone Touch Data

Gaining awareness of the user's affective states enables smartphones to support enriched interactions that are sensitive to the user's context. To accomplish this on smartphones, we propose a system that analyzes the user's text typing behavior using a semi-supervised deep learning pipeline for predicting affective states measured by valence, arousal, and dominance. Using a data collection study with 70 participants on text conversations designed to trigger different affective responses, we developed a variational auto-encoder to learn efficient feature embeddings of two-dimensional heat maps generated from touch data while participants engaged in these conversations. Using the learned embedding in a cross-validated analysis, our system predicted three levels (low, medium, high) of valence (AUC up to 0.84), arousal (AUC up to 0.82), and dominance (AUC up to 0.82). These results demonstrate the feasibility of our approach to accurately predict affective states based only on touch data.

Glissade: Generating Balance Shifting Feedback to Facilitate Auxiliary Digital Pen Input

This paper introduces Glissade, a digital pen that generates balance shifting feedback by changing the weight distribution of the pen. A pulley system shifts a brass mass inside the pen to change the pen's center of mass and moment of inertia. When the mass is stationary, the pen delivers a constant yet natural sensation of weight, which can be used to convey a status. The pen can also generate a variety of haptic clues by actuating the mass according to the tilt or rotation of the pen, two commonly-used auxiliary pen input channels. Glissade demonstrates new possibilities that balance shifting feedback can bring to digital pen interactions. We validated the usability of this feedback by determining the recognizability of six balance patterns – a mix of static and dynamic patterns chosen based on our design considerations – in two controlled experiments. The results show that, on average, the participants could distinguish between the patterns with a 94.25% accuracy. At the end, we demonstrate a set of novel interactions enabled by Glissade and discuss the directions for future research.

Ambiguity-aware AI Assistants for Medical Data Analysis

Artificial intelligence (AI) assistants for clinical decision making show increasing promise in medicine. However, medical assessments can be contentious, leading to expert disagreement. This raises the question of how AI assistants should be designed to handle the classification of ambiguous cases. Our study compared two AI assistants that provide classification labels for medical time series data along with quantitative uncertainty estimates: conventional vs. ambiguity-aware. We simulated our ambiguity-aware AI based on real-world expert discussions to highlight cases likely to lead to expert disagreement, and to present arguments for conflicting classification choices. Our results demonstrate that ambiguity-aware AI can alter expert workflows by significantly increasing the proportion of contentious cases reviewed. We also found that the relevance of AI-provided arguments (selected from guidelines either randomly or by experts) affected experts' accuracy at revising AI-suggested labels. Our work contributes a novel perspective on the design of AI for contentious clinical assessments.

Becoming a Robot - Overcoming Anthropomorphism with Techno-Mimesis

Employing anthropomorphism in physical appearance and behavior is the most widespread strategy for designing social robots. In the present paper, we argue that imitating humans impedes the full exploration of robots' social abilities. In fact, their very 'thingness' (e.g., sensors, rationality) is able to create 'superpowers' that go beyond human abilities, such as endless patience. To better identify these special abilities, we develop a performative method called 'Techno-Mimesis' and explore it in a series of workshops with robot designers. Specifically, we create 'prostheses' to allow designers to transform themselves into their future robot to experience use cases from the robot's perspective, e.g., 'seeing' with a distance sensor rather than with eyes. This imperfect imitation helps designers to experience being human and being robot at the same time, making differences apparent and facilitating the discovery of a number of potential physical, cognitive, and communicational robotic superpowers.

Understanding what you feel: A Mobile Audio-Tactile System for Graphics Used at Schools with Students with Visual Impairment

A lot of information is nowadays presented graphically. However, students with blindness do not have access to visual information. Providing an alternative text is not always the appropriate solution as exploring graphics to discover information independently is a fundamental part of the learning process. In this work, we introduce a mobile audio-tactile learning environment, which facilitates the incorporation of real educational material. We evaluate our system by comparing three methods of interaction with tactile graphics: A tactile graphic augmented by (1) a document with key index information in Braille, (2) a digital document with key index information and (3) the TPad system, an audio-tactile solution meeting the specific needs within the school context. Our study shows that the TPad system is suitable for educational environments. Moreover, compared to the other methods TPad is faster to explore tactile graphics and it suggests a promising effect on the memorization of information.

Digital-Enabled Last Mile: A Study of Passenger Trips in Rural, Low-density Populated Areas

Public transportation in rural areas is difficult due to low numbers of passengers and diverse needs, also reflected in the last mile problem that points to the distance to access transportation hubs in order to connect with core networks of transportation. In this paper, we study public transportation in rural areas using a digital-enabled, demand-responsive service called Plustur. This service was recently introduced as an effort to increase mobility in underserved rural areas by creating routes ad-hoc to answer to the last mile(s). We study how passengers and drivers understand Plustur, as well as experience the role of passenger. Our findings show that Plustur is viewed as a benefit for autonomy of mobility in rural areas, however is lacking in addressing integration of modes of mobilities, flexibility and spontaneous trips. We contribute with design implications for digital multimodal mobility services.

Integrating the Digital and the Traditional to Deliver Therapy for Depression: Lessons from a Pragmatic Study

Traditional approaches to psychotherapy emphasise face-to-face contact between patients and therapists. In contrast, current computerised approaches tend to minimise this contact. This can limit the range of mental health difficulties for which computerised approaches are effective. Here, we explore an alternative approach that integrates face-to-face contact, electronic contact, online collaboration, and support for between-session activities. Our discussion is grounded in the design of a platform to deliver psychotherapy for depression. We report findings of an 11-month pragmatic study in which 17 patients received treatment for depression via the platform. Results show how design decisions had a significant impact on the dynamics of therapeutic sessions and the establishment of patient-therapist relationships. For example, the use of instant messaging for synchronous, in-session contact slowed communication, but also provided a valuable space for reflection and helped to maintain session focus. We discuss the impact of flexibility and the potential of integrated approaches to both enhance and reduce patient engagement.

"It's a scavenger hunt": Usability of Websites' Opt-Out and Data Deletion Choices

We conducted an in-lab user study with 24 participants to explore the usefulness and usability of privacy choices offered by websites. Participants were asked to find and use choices related to email marketing, targeted advertising, or data deletion on a set of nine websites that differed in terms of where and how these choices were presented. They struggled with several aspects of the interaction, such as selecting the correct page from a site's navigation menu and understanding what information to include in written opt-out requests. Participants found mechanisms located in account settings pages easier to use than options contained in privacy policies, but many still consulted help pages or sent email to request assistance. Our findings indicate that, despite their prevalence, privacy choices like those examined in this study are difficult for consumers to exercise in practice. We provide design and policy recommendations for making these website opt-out and deletion choices more useful and usable for consumers.

Chasm: A Screw Based Expressive Compact Haptic Actuator

We present a compact broadband linear actuator, Chasm, that renders expressive haptic feedback on wearable and handheld devices. Unlike typical motor-based haptic devices with integrated gearheads, Chasm utilizes a miniature leadscrew coupled to a motor shaft, thereby directly translating the high-speed rotation of the motor to the linear motion of a nut carriage without an additional transmission. Due to this simplicity, Chasm can render low-frequency skin-stretch and high-frequency vibrations, simultaneously and independently. We present the design of the actuator assembly and validate its electromechanical and perceptual performance. We then explore use cases and show design solutions for embedding Chasm in device prototypes. Finally, we report investigations with Chasm in two VR embodiments, i.e., in a headgear band to induce locomotion cues and in a handheld pointer to enhance dynamic manual interactions. Our explorations show wide use for Chasm in enhancing user interactions and experience in virtual and augmented settings.

TangibleCircuits: An Interactive 3D Printed Circuit Education Tool for People with Visual Impairments

We present a novel haptic and audio feedback device that allows blind and visually impaired (BVI) users to understand circuit diagrams. TangibleCircuits allows users to interact with a 3D printed tangible model of a circuit which provides audio tutorial directions while being touched. Our system comprises an automated parsing algorithm which extracts 3D printable models as well as an audio interfaces from a Fritzing diagram. To better understand the requirements of designing technology to assist BVI users in learning hardware computing, we conducted a series of formative inquiries into the accessibility limitations of current circuit tutorial technologies. In addition, we derived insights and design considerations gleaned from conducting a formal comparative user study to understand the effectiveness of TangibleCircuits as a tutorial system. We found that BVI users were better able to understand the geometric, spatial and structural circuit information using TangibleCircuits, as well as enjoyed learning with our tool.

Music Creation by Example

Short online videos have become the dominating media on social platforms. However, finding suitable music to accompany videos can be a challenging task to some video creators, due to copyright constraints, limitations in search engines, and required audio-editing expertise. One possible solution to these problems is to use AI music generation. In this paper we present a user interface (UI) paradigm that allows users to input a song to an AI engine and then interactively regenerate and mix AI-generated music. To arrive at this design, we conducted user studies with a total of 104 video creators at several stages of our design and development process. User studies supported the effectiveness of our approach and provided valuable insights about human-AI interaction as well as the design and evaluation of mixed-initiative interfaces in creative practice.

Infrastructural Speculations: Tactics for Designing and Interrogating Lifeworlds

This paper introduces "infrastructural speculations," an orientation toward speculative design that considers the complex and long-lived relationships of technologies with broader systems, beyond moments of immediate invention and design. As modes of speculation are increasingly used to interrogate questions of broad societal concern, it is pertinent to develop an orientation that foregrounds the "lifeworld" of artifacts-the social, perceptual, and political environment in which they exist. While speculative designs often imply a lifeworld, infrastructural speculations place lifeworlds at the center of design concern, calling attention to the cultural, regulatory, environmental, and repair conditions that enable and surround particular future visions. By articulating connections and affinities between speculative design and infrastructure studies research, we contribute a set of design tactics for producing infrastructural speculations. These tactics help design researchers interrogate the complex and ongoing entanglements among technologies, institutions, practices, and systems of power when gauging the stakes of alternate lifeworlds.

The Effectiveness of Visual and Audio Wayfinding Guidance on Smartglasses for People with Low Vision

Wayfinding is a critical but challenging task for people who have low vision, a visual impairment that falls short of blindness. Prior wayfinding systems for people with visual impairments focused on blind people, providing only audio and tactile feedback. Since people with low vision use their remaining vision, we sought to determine how audio feedback compares to visual feedback in a wayfinding task. We developed visual and audio wayfinding guidance on smartglasses based on de facto standard approaches for blind and sighted people and conducted a study with 16 low vision participants. We found that participants made fewer mistakes and experienced lower cognitive load with visual feedback. Moreover, participants with a full field of view completed the wayfinding tasks faster when using visual feedback. However, many participants preferred audio feedback because of its shorter learning curve. We propose design guidelines for wayfinding systems for low vision.

Exploring the Potential of an Intelligent Tutoring System for Sketching Fundamentals

Sketching is a practical and useful skill that can benefit communication and problem solving. However, it remains a difficult skill to learn because of low confidence and motivation among students and limited availability for instruction and personalized feedback among teachers. There is an need to improve the educational experience for both groups, and we hypothesized that integrating technology could provide a variety of benefits. We designed and developed an intelligent tutoring system for sketching fundamentals called Sketchtivity, and deployed it in to six existing courses at the high school and university level during the 2017-2018 school year. 268 students used the tool and produced more than 116,000 sketches of basic primitives. We conducted semi-structured interviews with the six teachers who implemented the software, as well as nine students from a course where the tool was used extensively. Using grounded theory, we found ten categories which unveiled the benefits and limitations of integrating an intelligent tutoring system for sketching fundamentals in to existing pedagogy.

Reinforcement Learning for the Adaptive Scheduling of Educational Activities

Adaptive instruction for online education can increase learning gains and decrease the work required of learners, instructors, and course designers. Reinforcement Learning (RL) is a promising tool for developing instructional policies, as RL models can learn complex relationships between course activities, learner actions, and educational outcomes. This paper demonstrates the first RL model to schedule educational activities in real time for a large online course through active learning. Our model learns to assign a sequence of course activities while maximizing learning gains and minimizing the number of items assigned. Using a controlled experiment with over 1,000 learners, we investigate how this scheduling policy affects learning gains, dropout rates, and qualitative learner feedback. We show that our model produces better learning gains using fewer educational activities than a linear assignment condition, and produces similar learning gains to a self-directed condition using fewer educational activities and with lower dropout rates.

Generating Audio-Visual Slideshows from Text Articles Using Word Concreteness

We present a system that automatically transforms text articles into audio-visual slideshows by leveraging the notion of word concreteness, which measures how strongly a word or phrase is related to some perceptible concept. In a formative study we learn that people not only prefer such audio-visual slideshows but find that the content is easier to understand compared to text articles or text articles augmented with images. We use word concreteness to select search terms and find images relevant to the text. Then, based on the distribution of concrete words and the grammatical structure of an article, we time-align selected images with audio narration obtained through text-to-speech to produce audio-visual slideshows. In a user evaluation we find that our concreteness-based algorithm selects images that are highly relevant to the text. The quality of our slideshows is comparable to slideshows produced manually using standard video editing tools, and people strongly prefer our slideshows to those generated using a simple keyword-search based approach.

EmoG: Supporting the Sketching of Emotional Expressions for Storyboarding

Storyboarding is an important ideation technique that uses sequential art to depict important scenarios of user experience. Existing data-driven support for storyboarding focuses on constructing user stories, but fail to address its benefit as a graphic narrative device. Instead, we propose to develop a data-driven design support tool that increases the expressiveness of user stories by facilitating sketching storyboards. To explore this, we focus on supporting the sketching of emotional expressions of characters in storyboards. In this paper, we present EmoG, an interactive system that generates sketches of characters with emotional expressions based on input strokes from the user. We evaluated EmoG with 21 participants in a controlled user study. The results showed that our tool has significantly better performance in usefulness, ease of use, and quality of results than the baseline system.

Awareness, Understanding, and Action: A Conceptual Framework of User Experiences and Expectations about Indoor Air Quality Visualizations

With the advent of new sensors and technologies, smart devices that monitor the level of indoor air quality (IAQ) are increasingly available to create a healthy home environment. However, little has been studied regarding design principles for effective IAQ visualizations to help better understand and improve IAQ. We analyzed Amazon reviews of IAQ monitors and their design components for IAQ visualizations. Based on our findings, we created a conceptual framework to explain the process of facilitating an effective IAQ visualization with a proposed set of design considerations in each stage. The process includes helping users easily understand what is happing to IAQ (awareness), what it means to them (understanding), and what to do with the information (action), which results in two outcomes, knowledge gain and emotional relief. We hope our framework can help practitioners and researchers in designing eco-feedback system and beyond to advance both research and practice.

Designing Voice Interfaces: Back to the (Curriculum) Basics

Voice user interfaces (VUIs) are rapidly increasing in popularity in the consumer space. This leads to a concurrent explosion of available applications for such devices, with many industries rushing to offer voice interactions for their products. This pressure is then transferred to interface designers; however, a large majority of designers have been only trained to handle the usability challenges specific to Graphical User Interfaces (GUIs). Since VUIs differ significantly in design and usability from GUIs, we investigate in this paper the extent to which current educational resources prepare designers to handle the specific challenges of VUI design. For this, we conducted a preliminary scoping scan and syllabi meta review of HCI curricula at more than twenty top international HCI departments, revealing that the current offering of VUI design training within HCI education is rather limited. Based on this, we advocate for the updating of HCI curricula to incorporate VUI design, and for the development of VUI-specific pedagogical artifacts to be included in new curricula.

RoomShift: Room-scale Dynamic Haptics for VR with Furniture-moving Swarm Robots

RoomShift is a room-scale dynamic haptic environment for virtual reality, using a small swarm of robots that can move furniture. RoomShift consists of nine shape-changing robots: Roombas with mechanical scissor lifts. These robots drive beneath a piece of furniture to lift, move and place it. By augmenting virtual scenes with physical objects, users can sit on, lean against, place and otherwise interact with furniture with their whole body; just as in the real world. When the virtual scene changes or users navigate within it, the swarm of robots dynamically reconfigures the physical environment to match the virtual content. We describe the hardware and software implementation, applications in virtual tours and architectural design and interaction techniques.

Explain like I am a Scientist: The Linguistic Barriers of Entry to r/science

As an online community for discussing research findings, r/science has the potential to contribute to science outreach and communication with a broad audience. Yet previous work suggests that most of the active contributors on r/science are science-educated people rather than a lay general public. One potential reason is that r/science contributors might use a different, more specialized language than used in other subreddits. To investigate this possibility, we analyzed the language used in more than 68 million posts and comments from 12 subreddits from 2018. We show that r/science uses a specialized language that is distinct from other subreddits. Transient (newer) authors of posts and comments on r/science use less specialized language than more frequent authors, and those that leave the community use less specialized language than those that stay, even when comparing their first comments. These findings suggest that the specialized language used in r/science has a gatekeeping effect, preventing participation by people whose language does not align with that used in r/science. By characterizing r/science's specialized language, we contribute guidelines and tools for increasing the number of contributors in r/science.

A Design Engineering Approach for Quantitatively Exploring Context-Aware Sentence Retrieval for Nonspeaking Individuals with Motor Disabilities

Nonspeaking individuals with motor disabilities typically have very low communication rates. This paper proposes a design engineering approach for quantitatively exploring context-aware sentence retrieval as a promising complementary input interface, working in tandem with a word-prediction keyboard. We motivate the need for complementary design engineering methodology in the design of augmentative and alternative communication and explain how such methods can be used to gain additional design insights. We then study the theoretical performance envelopes of a context-aware sentence retrieval system, identifying potential keystroke savings as a function of the parameters of the subsystems, such as the accuracy of the underlying auto-complete word prediction algorithm and the accuracy of sensed context information under varying assumptions. We find that context-aware sentence retrieval has the potential to provide users with considerable improvements in keystroke savings under reasonable parameter assumptions of the underlying subsystems. This highlights how complementary design engineering methods can reveal additional insights into design for augmentative and alternative communication.

Expanding Modes of Reflection in Design Futuring

Design futuring approaches, such as speculative design, design fiction and others, seek to (re)envision futures and explore alternatives. As design futuring becomes established in HCI design research, there is an opportunity to expand and develop these approaches. To that end, by reflecting on our own research and examining related work, we contribute five modes of reflection. These modes concern formgiving, temporality, researcher positionality, real-world engagement, and knowledge production. We illustrate the value of each mode through careful analysis of selected design exemplars and provide questions to interrogate the practice of design futuring. Each reflective mode offers productive resources for design practitioners and researchers to articulate their work, generate new directions for their work, and analyze their own and others' work.

Progression Maps: Conceptualizing Narrative Structure for Interaction Design Support

Interactive narratives are frequently designed for learning and training applications, such as social training. In these contexts, designers may be inexperienced in storytelling and interaction design, and it may be difficult to quickly build an effective experience, even for experienced designers. Designers often approach this problem through iterative design. To augment and reduce iteration, we argue for the utility of employing models to reason about, evaluate, and improve designs. While there has been much previous work on interactive narrative models, none of them capture aspects of the interaction design necessary for testing and evaluation. In this paper we propose a new computational model called Progression Maps, which abstracts interaction design elements of the narrative's structure and visualizes its interaction properties. We report on the model, its implementation, and two studies evaluating its use. Our results demonstrate Progression Maps' effectiveness in communicating the underlying design through an easily understandable visualization.

Designers in White Coats: Deploying Ovum, a Fertility Tracking Device

As self-tracking practices continue to proliferate, there has been a call for a consideration of how the design of these devices influence the users experience of themselves and their bodies beyond utility, efficacy and accuracy. The research product Ovum was designed to facilitate a DIY, shared, domestic experience, rather than an expert-led, individual, clinical experience of fertility tracking. Ovum uses the method of saliva sampling to determine ovulation. This paper unpacks the findings from a three-month long deployment of Ovum with seven couples trying to conceive. Besides an evaluation of the device in terms of the three experiential qualities aimed for in the design process, we report on the consequences of executing a design deployment that resembles a clinical trial. We contribute our experience in order to develop an understanding of how designing for the body places interaction designers in novel and complex situations.

Amazon vs. My Brother: How Users of Shared Smart Speakers Perceive and Cope with Privacy Risks

With the rapid adoption of smart speakers in people's homes, there is a corresponding increase in users' privacy and security concerns. In contrast to previous studies of users' concerns about smart speakers' divulging private information to their manufacturers, our study focused on investigating users' concerns with regard to housemates and external entities. We conducted semi-structured interviews with 26 participants living in 21 households. Our results suggest that users often have an inadequate understanding of what data their smart speakers makes available to all users and what is kept private. Although participants expressed different privacy concerns about their housemates and external entities, they adopted similar, yet suboptimal, risk management strategies. We provide recommendations for future speaker design to support more optimal coping with the perceived risks.

Opportunities and Challenges in Involving Users in Project-Based HCI Education

Users are fundamental to HCI. However, little is known about how HCI education introduces students to working with users, particularly those different from themselves. To better understand design students' engagement, reactions, and reflections with users, we investigate a case study of a graduate-level 10-week prototyping studio course that partnered with a children's co-design team. HCI students participated in two co-design sessions with children to design a STEM learning experience for youth. We conducted participant observations, interviews with 14 students, and analyzed final artifacts. Our findings demonstrate the communication challenges and strategies students experienced, how students observed issues of power dynamics, and students' perceived value in engaging with users. We contribute empirical evidence of how HCI students directly interact with target users, principles for reflective HCI pedagogy, and highlight the need for more intentional investigation into HCI educational practice.

ReFind: Design, Lived Experience and Ongoingness in Bereavement

We describe the design and use of ReFind, a handheld artefact made for people who are bereaved and are ready to re-explore their relationship to the deceased person. ReFind was made within a project seeking to develop new ways to curate and create digital media to support ongoingness - an active, dynamic component of continuing bonds. We draw on bereavement theory and care championing practices that enable a continued sense of connection between someone bereaved and a person who has died. We present the design development of ReFind and the lived experience of the piece by the first author. We discuss our wider methodology which includes autobiographical design and reflections on if and how the piece supported ongoing connections, the challenges faced, and insights gained.

Foundations for Designing Public Interactive Displays that Provide Value to Users

Public interactive displays (PID) are a promising technology for providing information and collecting feedback in public spaces. Research on PIDs has shown that, like all public displays, their efficacy is reduced by display blindness. Rather than increase the visual attention-grabbing nature of PIDs, we propose that additional understanding is required around how and when these displays are able to offer value to users. We tackle this through a systematic analysis of PID studies published in the literature, which led to 9 aspects of value across 4 factors: people, location, community, and time. We discuss the identified aspects and their utility for the design of PIDs through a review of our own deployments carried out by 4 different labs across 5 countries. We conclude with a set of recommendations for identifying and optimising the intended value of future PIDs.

Paths Explored, Paths Omitted, Paths Obscured: Decision Points & Selective Reporting in End-to-End Data Analysis

Drawing reliable inferences from data involves many, sometimes arbitrary, decisions across phases of data collection, wrangling, and modeling. As different choices can lead to diverging conclusions, understanding how researchers make analytic decisions is important for supporting robust and replicable analysis. In this study, we pore over nine published research studies and conduct semi-structured interviews with their authors. We observe that researchers often base their decisions on methodological or theoretical concerns, but subject to constraints arising from the data, expertise, or perceived interpretability. We confirm that researchers may experiment with choices in search of desirable results, but also identify other reasons why researchers explore alternatives yet omit findings. In concert with our interviews, we also contribute visualizations for communicating decision processes throughout an analysis. Based on our results, we identify design opportunities for strengthening end-to-end analysis, for instance via tracking and meta-analysis of multiple decision paths.

Robustness of Eye Movement Biometrics Against Varying Stimuli and Varying Trajectory Length

Recent results suggest that biometric identification based on human's eye movement characteristics can be used for authentication. In this paper, we present three new methods and benchmark them against the state-of-the-art. The best of our new methods improves the state-of-the-art performance by 5.2 percentage points. Furthermore, we investigate some of the factors that affect the robustness of the recognition rate of different classifiers on gaze trajectories, such as the type of stimulus and the tracking trajectory length. We find that the state-of-the-art method only works well when using the same stimulus for testing that was used for training. By contrast, our novel method more than doubles the identification accuracy for these transfer cases. Furthermore, we find that with only 90 seconds of eye tracking data, 86.7% accuracy can be achieved.

Manufacturing Change: The Impact of Virtual Environments on Real Organizations

Manufacturing workplaces are becoming sites of intense change as technologies like IoT and AR/VR are beginning to make deep inroads into how complex products are engi-neered and assembled. These categories of technologies are becoming prominent in manufacturing because they offer potential solutions to the problems of unskilled labor and workforce shortages. Technology has the potential to shift manufacturing in both large and small ways, to better un-derstand how a manufacturing organization might appropri-ate VR, we ran a study with a global aviation manufacturer headquartered the United States. To document the changing nature of work via this class of technologies we conducted a VR study which facilitated access to participant observation and interviews (n=21). Our findings provide initial insights into the organizational impact of VR on human perfor-mance augmentation and skill acquisition revealing the larger infrastructural challenges facing the adoption of con-sumer grade smart technologies in industrial workplace settings.

Heartbeats in the Wild: A Field Study Exploring ECG Biometrics in Everyday Life

This paper reports on an in-depth study of electrocardiogram (ECG) biometrics in everyday life. We collected ECG data from 20 people over a week, using a non-medical chest tracker. We evaluated user identification accuracy in several scenarios and observed equal error rates of 9.15% to 21.91%, heavily depending on 1) the number of days used for training, and 2) the number of heartbeats used per identification decision. We conclude that ECG biometrics can work in the wild but are less robust than expected based on the literature, highlighting that previous lab studies obtained highly optimistic results with regard to real life deployments. We explain this with noise due to changing body postures and states as well as interrupted measures. We conclude with implications for future research and the design of ECG biometrics systems for real world deployments, including critical reflections on privacy.

Augmented Reality to Enable Users in Learning Case Grammar from Their Real-World Interactions

Augmented Reality (AR) provides a unique opportunity to situate learning content in one's environment. In this work, we investigated how AR could be developed to provide an interactive context-based language learning experience. Specifically, we developed a novel handheld-AR app for learning case grammar by dynamically creating quizzes, based on real-life objects in the learner's surroundings. We compared this to the experience of learning with a non-contextual app that presented the same quizzes with static photographic images. Participants found AR suitable for use in their everyday lives and enjoyed the interactive experience of exploring grammatical relationships in their surroundings. Nonetheless, Bayesian tests provide substantial evidence that the interactive and context-embedded AR app did not improve case grammar skills, vocabulary retention, and usability over the experience with equivalent static images. Based on this, we propose how language learning apps could be designed to combine the benefits of contextual AR and traditional approaches.

Retroactive Transfer Phenomena in Alternating User Interfaces

We investigated retroactive transfer when users alternate between different interfaces. Retroactive transfer is the influence of a newly learned interface on users' performance with a previously learned interface. In an interview study, participants described their experiences when alternating between different interfaces, e.g. different operating systems, devices or techniques. Negative retroactive transfer related to text entry was the most frequently reported incident. We then reported a laboratory experiment that investigated the impact of similarity between two abstract keyboard layouts, and the number of alternations between them, on retroactive interference. Results indicated that even small changes in the interference interface produced a significant performance drop for the entire previously learned interface. The amplitude of this performance drop decreases with the number of alternations. We suggest that retroactive transfer should receive more attention in HCI, as the ubiquitous nature of interactions across applications and systems requires users to increasingly alternate between similar interfaces.

Designing and Evaluating Calmer, a Device for Simulating Maternal Skin-to-Skin Holding for Premature Infants

We describe the design and deployment of Calmer, a technology that simulates key aspects of maternal skin-to-skin holding for prematurely born infants: its inspiration, approach, physical design, and introduction into the Neonatal Intensive Care Unit. Maternal skin-to-skin holding can mitigate neonatal pain during medical procedures by as much as 50%, which can improve weight gain, sleep and later development. However, parents cannot always be present, and some infants are too fragile to be held. Interventions targeting this gap could be perceived as supplanting the mother in this intimate role, exposing her to depression and endangering her maternal bond. Over 10 years, we iteratively developed Calmer and demonstrated infant health benefit in a randomized clinical trial. Here, we report and reflect on pursuing this goal in a socially and technologically complex context: constraints, strategies, features, reception of the device, and surprises, such as leading to mothers feeling channeled rather than replaced.

"It's in my other hand!" – Studying the Interplay of Interaction Techniques and Multi-Tablet Activities

Cross-device interaction with tablets is a popular topic in HCI research. Recent work has shown the benefits of including multiple devices into users' workflows while various interaction techniques allow transferring content across devices. However, users are only reluctantly using multiple devices in combination. At the same time, research on cross-device interaction struggles to find a frame of reference to compare techniques or systems. In this paper, we try to address these challenges by studying the interplay of interaction techniques, device utilization, and task-specific activities in a user study with 24 participants from different but complementary angles of evaluation using an abstract task, a sensemaking task, and three interaction techniques. We found that different interaction techniques have a lower influence than expected, that work behaviors and device utilization depend on the task at hand, and that participants value specific aspects of cross-device interaction.

CollabAR – Investigating the Mediating Role of Mobile AR Interfaces on Co-Located Group Collaboration

Mobile Augmented Reality (AR) technology is enabling new applications for different domains including architecture, education or medical work. As AR interfaces project digital data, information and models into the real world, it allows for new forms of collaborative work. However, despite the wide availability of AR applications, very little is known about how AR interfaces mediate and shape collaborative practices. This paper presents a study which examines how a mobile AR (M-AR) interface for inspecting and discovering AR models of varying complexity impacts co-located group practices. We contribute new insights into how current mobile AR interfaces impact co-located collaboration. Our results show that M-AR interfaces induce high mental load and frustration, cause a high number of context switches between devices and group discussion, and overall leads to a reduction in group interaction. We present design recommendations for future work focusing on collaborative AR interfaces.

Political Hashtags & the Lost Art of Democratic Discourse

In this work, we investigate whether and how the presence of political hashtags in social media news articles influences the way people discuss news content. Specifically, we examine how political hashtags in news posts act as a design characteristic that affects the quality of online discourse. We use a randomized control experiment to assess how the presence versus absence of political hashtags (particularly the most prevalently used #MeToo and #BlackLivesMatter) in social media news posts shapes discourse across a general audience (n=3205). Key findings show differences in topical focus, emotional tone of discourse, and rhetorical styles between commenters who were shown news posts with political hashtags versus those shown news posts without the hashtags. Compared to the control group, those shown hashtagged news posts heavily focus on the politics of the hashtag, use more words associated with fear, anger, and disgust in their comments, and exhibit black-and-white rhetoric and less emotionally temperate expressions in their arguments.

ProtoSpray: Combining 3D Printing and Spraying to Create Interactive Displays with Arbitrary Shapes

ProtoSpray is a fabrication method that combines 3D printing and spray coating, to create interactive displays of arbitrary shapes. Our approach makes novel use of 3D printed conductive channels to create base electrodes on 3D shapes. This is then combined with spraying active materials to produce illumination. We demonstrate the feasibility and benefits of this combined approach in 6 evaluations exploring different shaped topologies. We analyze factors such as spray orientations, surface topologies and printer resolutions, to discuss how spray nozzles can be integrated into traditional 3D printers. We present a series of ProtoSprayed objects demonstrating how our technique goes beyond existing fabrication techniques by allowing creation of displays on objects with curvatures as complex as a Mobius strip. Our work provides a platform to empower makers to use displays as a fabrication material.

GAZED– Gaze-guided Cinematic Editing of Wide-Angle Monocular Video Recordings

We present GAZED– eye GAZe-guided EDiting for videos captured by a solitary, static, wide-angle and high-resolution camera. Eye-gaze has been effectively employed in computational applications as a cue to capture interesting scene content; we employ gaze as a proxy to select shots for inclusion in the edited video. Given the original video, scene content and user eye-gaze tracks are combined to generate an edited video comprising cinematically valid actor shots and shot transitions to generate an aesthetic and vivid representation of the original narrative. We model cinematic video editing as an energy minimization problem over shot selection, whose constraints capture cinematographic editing conventions. Gazed scene locations primarily determine the shots constituting the edited video. Effectiveness of GAZED against multiple competing methods is demonstrated via a psychophysical study involving 12 users and twelve performance videos.

On Being Iterated: The Affective Demands of Design Participation

Iteration is a central feature of most HCI design methods, creating as it does opportunities for engagements with stakeholder groups. But what does iteration demand of those groups? Under what conditions do iterative engagements arise, and with what stakes? Building on experiences with Aboriginal Australian communities, and drawing on feminist and decolonial thinking, we examine the nature of iteration for HCI and how it frames encounters between design and use, with a focus on the affective dimension of engagement in iterative design processes.

Classification of Functional Attention in Video Meetings

Participants in video meetings have long struggled with asymmetrical attention levels, especially when participants are distributed unevenly. While technological advances offer exciting opportunities to augment remote users' attention, the phenomenological complexity of attention means that to design attention-fostering features we must first understand what aspects of it are functionally meaningful to support. In this paper, we present a functional classification of observable attention for video meetings. The classification was informed by two studies on sense-making and selectiveness of attention in work meetings. It includes categories of attention accessible for technological support, their functions in a meeting process, and meeting-related activities that correspond to these functions. This classification serves as a multi-level representation of attention and informs the design of features aiming to support remote participants' attention in video meetings.

Collaborative or Simply Uncaged? Understanding Human-Cobot Interactions in Automation

Collaborative robots, or cobots, represent a breakthrough technology designed for high-level (e.g. collaborative) interactions between workers and robots with capabilities for flexible deployment in industries such as manufacturing. Understanding how workers and companies use and integrate cobots is important to inform the future design of cobot systems and educational technologies that facilitate effective worker-cobot interaction. Yet, little is known about typical training for collaboration and the application of cobots in manufacturing. To close this gap, we interviewed nine experts in manufacturing about their experience with cobots. Our thematic analysis revealed that, contrary to the envisioned use, experts described most cobot applications as only low-level (e.g. pressing start/stop buttons) interactions with little flexible deployment, and experts felt traditional robotics skills were needed for collaborative and flexible interaction with cobots. We conclude with design recommendations for improved future robots, including programming and interface designs, and educational technologies to support collaborative use.

Characterizing Twitter Users Who Engage in Adversarial Interactions against Political Candidates

Social media provides a critical communication platform for political figures, but also makes them easy targets for harassment. In this paper, we characterize users who adversarially interact with political figures on Twitter using mixed-method techniques. The analysis is based on a dataset of 400 thousand users' 1.2 million replies to 756 candidates for the U.S. House of Representatives in the two months leading up to the 2018 midterm elections. We show that among moderately active users, adversarial activity is associated with decreased centrality in the social graph and increased attention to candidates from the opposing party. When compared to users who are similarly active, highly adversarial users tend to engage in fewer supportive interactions with their own party's candidates and express negativity in their user profiles. Our results can inform the design of platform moderation mechanisms to support political figures countering online harassment.

Private Responses for Public Sharing: Understanding Self-Presentation and Relational Maintenance via Stories in Social Media

With nearly two billion users, social media Stories-an ephemeral format of sharing-are increasingly popular and projected to overtake sharing via public feeds. Sharing via Stories differs from Feeds sharing by removing the visible feedback (e.g. "likes" and "comments") which has come to characterize social media. Given the salience of responses visibility to self-presentation and relational maintenance in social media literature, we conducted semi-structured interviews (N = 22) to explore how people understand these processes when using Stories. We find that users have lower expectations for responses with Stories and experience lower pressure for self-presentation. This fosters more frequent sharing and a sense of daily connectedness, which strong ties can find valuable. Finally, the act of viewing takes on new significance of signaling attention when made known to the sharer. Our findings point to the importance of effort and attention in understanding responses on social media.

A User Study on Mixed Reality Remote Collaboration with Eye Gaze and Hand Gesture Sharing

Supporting natural communication cues is critical for people to work together remotely and face-to-face. In this paper we present a Mixed Reality (MR) remote collaboration system that enables a local worker to share a live 3D panorama of his/her surroundings with a remote expert. The remote expert can also share task instructions back to the local worker using visual cues in addition to verbal communication. We conducted a user study to investigate how sharing augmented gaze and gesture cues from the remote expert to the local worker could affect the overall collaboration performance and user experience. We found that by combing gaze and gesture cues, our remote collaboration system could provide a significantly stronger sense of co-presence for both the local and remote users than using the gaze cue alone. The combined cues were also rated significantly higher than the gaze in terms of ease of conveying spatial actions.

Will Deleting History Make Alexa More Trustworthy?: Effects of Privacy and Content Customization on User Experience of Smart Speakers

"Always-on" smart speakers have raised privacy and security concerns, to address which vendors have introduced customizable privacy settings. But, does the act of customizing one's privacy preferences have any effects on user experience and trust? To address this question, we developed an app for Amazon Alexa and conducted a user study (N = 90). Our data show that the affordance to customize privacy settings enhances trust and usability for regular users, while it has adverse effects on power users. In addition, only enabling privacy-setting customization without allowing content customization negatively affects trust among users with higher privacy concerns. When they can customize both content and privacy settings, user trust is highest. That is, while privacy customization may cause reactance among power users, allowing privacy-concerned individuals to simultaneously customize content can help to alleviate the resultant negative effect on trust. These findings have implications for designing more privacy-sensitive and trustworthy smart speakers.

MagneLayer: Force Field Fabrication by Layered Magnetic Sheets

Magnets are very useful for the rapid prototyping of haptic interactions. However, it is difficult to arrange fine and complex magnetic fields rapidly. Therefore, we invented a method for fabricating complex geometric magnetic patterns by overlaying multiple magnetic rubber sheets. This method resolves the tradeoff between magnetized pattern complexity and the time required for magnetization. By layering multiple magnetic sheets that have simple magnetic patterns, various types of geometric magnetic patterns, such as checkered and diamond ones, can be generated on the top surface. By applying superposed magnetic fields, various types of tactile stimuli and haptic interaction can be created rapidly. Furthermore, the superposed magnetic fields can be changed dynamically by rotating the layered magnetic sheets. In this paper, we clarify the material requirements and describe the design method for creating these geometric magnetic patterns. We also demonstrate several of their applications.

GRIDS: Interactive Layout Design with Integer Programming

Grid layouts are used by designers to spatially organise user interfaces when sketching and wireframing. However, their design is largely time consuming manual work. This is challenging due to combinatorial explosion and complex objectives, such as alignment, balance, and expectations regarding positions. This paper proposes a novel optimisation approach for the generation of diverse grid-based layouts. Our mixed integer linear programming (MILP) model offers a rigorous yet efficient method for grid generation that ensures packing, alignment, grouping, and preferential positioning of elements. Further, we present techniques for interactive diversification, enhancement, and completion of grid layouts. These capabilities are demonstrated using GRIDS, a wireframing tool that provides designers with real-time layout suggestions. We report findings from a ratings study (N = 13) and a design study (N = 16), lending evidence for the benefit of computational grid generation during early stages of design.

Too Hot to Handle: An Evaluation of the Effect of Thermal Visual Representation on User Grasping Interaction in Virtual Reality

Influence of interaction fidelity and rendering quality on perceived user experience have been largely explored in Virtual Reality (VR). However, differences in interaction choices triggered by these rendering cues have not yet been explored. We present a study analysing the effect of thermal visual cues and contextual information on 50 participants' approach to grasp and move a virtual mug. This study comprises 3 different temperature cues (baseline empty, hot and cold) and 4 contextual representations; all embedded in a VR scenario. We evaluate 2 different hand representations (abstract and human) to assess grasp metrics. Results show temperature cues influenced grasp location, with the mug handle being predominantly grasped with a smaller grasp aperture for the hot condition, while the body and top were preferred for baseline and cold conditions.

Trust versus Privacy: Using Connected Car Data in Peer-to-Peer Carsharing

Trust is the lubricant of the sharing economy. This is true especially in peer-to-peer carsharing, in which one leaves a highly valuable good to a stranger in the hope of getting it back unscathed. Nowadays, ratings of other users are major mechanisms for establishing trust. To foster uptake of peer-to-peer carsharing, connected car technology opens new possibilities to support trust-building, e.g., by adding driving behavior statistics to users' profiles. However, collecting such data intrudes into rentees' privacy. To explore the tension between the need for trust and privacy demands, we conducted three focus group and eight individual interviews. Our results show that connected car technologies can increase trust for car owners and rentees not only before but also during and after rentals. The design of such systems must allow a differentiation between information in terms of type, the context, and the negotiability of information disclosure.

Evaluation of a Financial Portfolio Visualization using Computer Displays and Mixed Reality Devices with Domain Experts

With the advent of mixed reality devices such as the Microsoft HoloLens, developers have been faced with the challenge to utilize the third dimension in information visualization effectively. Research on stereoscopic devices has shown that three-dimensional representation can improve accuracy in specific tasks (e.g., network visualization). Yet, so far the field has remained mute on the underlying mechanism. Our study systematically investigates the differences in user perception between a regular monitor and a mixed reality device. In a real-life within-subject experiment in the field with twenty-eight investment bankers, we assessed subjective and objective task performance with two- and three-dimensional systems, respectively. We tested accuracy with regard to position, size, and color using single and combined tasks. Our results do not show a significant difference in accuracy between mixed-reality and standard 2D monitor visualizations.

Virtually-Extended Proprioception: Providing Spatial Reference in VR through an Appended Virtual Limb

Selecting targets directly in the virtual world is difficult due to the lack of haptic feedback and inaccurate estimation of egocentric distances. Proprioception, the sense of self-movement and body position, can be utilized to improve virtual target selection by placing targets on or around one's body. However, its effective scope is limited closely around one's body. We explore the concept of virtually-extended proprioception by appending virtual body parts mimicking real body parts to users' avatars, to provide spatial reference to virtual targets. Our studies suggest that our approach facilitates more efficient target selection in VR as compared to no reference or using an everyday object as reference. Besides, by cultivating users' sense of ownership on the appended virtual body part, we can further enhance target selection performance. The effects of transparency and granularity of the virtual body part on target selection performance are also discussed.

Un-authorised View: Leveraging Volunteer Expertise in Heritage

Volunteers are an underused but important resource in presenting plural heritages within large heritage organizations. We report on a qualitative study at a heritage site in the UK which combined explorations of volunteers' practice and digital design. The study comprised of observational fieldwork with co-creative activities across eight linked workshops, where we explored the site with volunteers, and how we might leverage existing working structures to make new design prototypes. Our collective account contributes new insights on working with volunteers and the opportunities that arise from acknowledging them as genius loci - recognising them as experts of their own experience and capturing and supporting their skills as storytellers. Working with the volunteering staff in a co-design process we created innovative designs including our Un-authorised View, which draws out the unique perspectives and the personal stories at heritage destinations.

Chameleon: Bringing Interactivity to Static Digital Documents

Documents such as presentations, instruction manuals, and research papers are disseminated using various file formats, many of which barely support the incorporation of interactive content. To address this lack of interactivity, we present Chameleon, a system-wide tool that combines computer vision algorithms used for image identification with an open database format to allow for the layering of dynamic content. Using Chameleon, static documents can be easily upgraded by layering user-generated interactive content on top of static images, all while preserving the original static document format and without modifying existing applications. We describe the development of Chameleon, including the design and evaluation of vision-based image replacement algorithms, the new document-creation pipeline as well as a user study evaluating Chameleon.

Exploring The Future of Data-Driven Product Design

Connected devices present new opportunities to advance design through data collection in the wild, similar to the way digital services evolve through analytics. However, it is still unclear how live data transmitted by connected devices informs the design of these products, going beyond performance optimisation to support creative practices. Design can be enriched by data captured by connected devices, from usage logs to environmental sensors, and data about the devices and people around them. Through a series of workshops, this paper contributes industry and academia perspectives on the future of data-driven product design. We highlight HCI challenges, issues and implications, including sensemaking and the generation of design insight. We further challenge current notions of data-driven design and envision ways in which future HCI research can develop ways to work with data in the design process in a connected, rich, human manner.

Alexa as Coach: Leveraging Smart Speakers to Build Social Agents that Reduce Public Speaking Anxiety

Public speaking anxiety is one of the most common social phobias. We explore the feasibility of using a conversational agent to reduce this anxiety. We developed a public-speaking tutor on the Amazon Alexa platform that enables users to engage in cognitive reconstruction exercises. We also investigated how the sociability of the agent might affect its performance as a tutor. A user study of 53 college students with fear of public speaking showed that the interaction with the agent served to assuage pre-speech state anxiety. Agent sociability improved the sense of interpersonal closeness, which was associated with lower pre-speech anxiety. Moreover, sociability of the agent increased participants' satisfaction and their willingness to continue engagement. Our findings, thus, have implications not only for addressing public speaking anxiety in a scalable way but also for the design of future conversational agents using smart speaker platforms.

Do You Feel Like Passing Through Walls?: Effect of Self-Avatar Appearance on Facilitating Realistic Behavior in Virtual Environments

Preventing users from walking through virtual boundaries (e.g., walls) is an important issue to be addressed in room-scale virtual environments (VEs), considering the safety and design limitations. Sensory feedback from wall collisions has been shown to be effective; however, it can disrupt the immersion. We assumed that a greater sense of presence would discourage users from walking through walls and conducted a two-factor between-subjects experiment (N = 92) that controls the anthropomorphism (realistic or abstract) and visibility (full-body or hand-only) of self-avatars. We analyzed the participants' behaviors and the moment they first penetrated the wall in game-like VEs that gradually instigated participants to penetrate the walls. The results showed that the realistic full-body self-avatar was the most effective for discouraging the participants from penetrating the walls. Furthermore, the participants with lower presence tended to walk through the walls sooner. This study can contribute to applications that require realistic user responses in VEs.

Automatic Text Simplification Tools for Deaf and Hard of Hearing Adults: Benefits of Lexical Simplification and Providing Users with Autonomy

Automatic Text Simplification (ATS), which replaces text with simpler equivalents, is rapidly improving. While some research has examined ATS reading-assistance tools, little has examined preferences of adults who are deaf or hard-of-hearing (DHH), and none empirically evaluated lexical simplification technology (replacement of individual words) with these users. Prior research has revealed that U.S. DHH adults have lower reading literacy on average than their hearing peers, with unique characteristics to their literacy profile. We investigate whether DHH adults perceive a benefit from lexical simplification applied automatically or when users are provided with greater autonomy, with on-demand control and visibility as to which words are replaced. Formative interviews guided the design of an experimental study, in which DHH participants read English texts in their original form and with lexical simplification applied automatically or on-demand. Participants indicated that they perceived a benefit form lexical simplification, and they preferred a system with on-demand simplification.

Whither Humane-Computer Interaction? Adult and Child Value Conflicts in the Biometric Fingerprinting for Food

This paper reports on the value conflicts that beneficiaries experience when engaging in the monthly ritual of the biometric authentication of their fingerprints to claim state-sponsored food entitlements in India. Drawing on value-based orientations to HCI inquiry, the study locates the interactions around the biometric process to illustrate the ways in which beneficiaries find their values of time, dignity, and privacy, consistently disregarded by the interactive demands of the biometric system. Additionally, to cope with these value conflicts, some beneficiaries pass on the responsibilities of completing the biometric process to the children in their families. While adult beneficiaries are vocal and articulate about the value tensions in their lives, children cope with the anxieties of interacting with the biometric process, silently; even as they experience conflicts in their education, play, and study time.

Augmented Reality for Older Adults: Exploring Acceptability of Virtual Coaches for Home-based Balance Training in an Aging Population

Balance training has been shown to be effective in reducing risks of falling, which is a major concern for older adults. Usually, exercise programs are individually prescribed and monitored by physiotherapeutic or medical experts. Unfortunately, supervision and motivation of older adults during home-based exercises cannot be provided on a large scale, in particular, considering an ageing population. Augmented reality (AR) in combination with virtual coaches could provide a reasonable solution to this challenge.

We present a first investigation of the acceptance of an AR coaching system for balance training, which can be performed at home. In a human-centered design approach we developed several mock-ups and prototypes, and evaluated them with 76 older adults. The results suggest that older adults find the system encouraging and stimulating. The virtual coach is perceived as an alive, calm, intelligent, and friendly human. However, usability of the entire AR system showed a significant negative correlation with participants' age.

Faces of Focus: A Study on the Facial Cues of Attentional States

Automatically detecting attentional states is a prerequisite for designing interventions to manage attention - knowledge workers' most critical resource. As a first step towards this goal, it is necessary to understand how different attentional states are made discernible through visible cues in knowledge workers. In this paper, we demonstrate the important facial cues to detect attentional states by evaluating a data set of 15 participants that we tracked over a whole workday, which included their challenge and engagement levels. Our evaluation shows that gaze, pitch, and lips part action units are indicators of engaged work; while pitch, gaze movements, gaze angle, and upper-lid raiser action units are indicators of challenging work. These findings reveal a significant relationship between facial cues and both engagement and challenge levels experienced by our tracked participants. Our work contributes to the design of future studies to detect attentional states based on facial cues.

Why do people watch others eat food? An Empirical Study on the Motivations and Practices of Mukbang Viewers

We present a mixed-methods study of viewers on their practices and motivations around watching mukbang — video streams of people eating large quantities of food. Viewers' experiences provide insight on future technologies for multisensorial video streams and technology-supported commensality (eating with others). We surveyed 104 viewers and interviewed 15 of them about their attitudes and reflections on their mukbang viewing habits, their physiological aspects of watching someone eat, and their perceived social relationship with mukbangers. Based on our findings, we propose design implications for remote commensality, and for synchronized multisensorial video streaming content.

The Care Work of Access

Current approaches to AI and Assistive Technology (AT) often foreground task completion over other encounters such as expressions of care. Our paper challenges and complements such task-completion approaches by attending to the care work of access-the continual affective and emotional adjustments that people make by noticing and attending to one another. We explore how this work impacts encounters among people with and without vision impairments who complete tasks together. We find that bound up in attempts to get things done are concerns for one another and how well people are doing together. Reading this work through emerging disability studies and feminist STS scholarship, we account for two important forms of work that give rise to access: (1) mundane attunements and (2) non-innocent authorizations. Together these processes work as sensitizing concepts to help HCI scholars account for the ways that intelligent ATs both produce access while sometimes subverting people with disabilities.

"Nobody Speaks that Fast!" An Empirical Study of Speech Rate in Conversational Agents for People with Vision Impairments

The number of people with vision impairments using Conversational Agents (CAs) has increased because of the potential of this technology to support them. As many visually impaired people are accustomed to understanding fast speech, most screen readers or voice assistant systems offer speech rate settings. However, current CAs are designed to interact at a human-like speech rate without considering their accessibility. In this study, we tried to understand how people with vision impairments use CA at a fast speech rate. We conducted a 20-day in-home study that examined the CA use of 10 visually impaired people at default and fast speech rates. We investigated the difference in visually impaired people's CA use with different speech rates and their perception toward CA at each rate. Based on these findings, we suggest considerations for the future design of CA speech rate for those with visual impairments.

Examining the Adoption and Abandonment of Security, Privacy, and Identity Theft Protection Practices

Users struggle to adhere to expert-recommended security and privacy practices. While prior work has studied initial adoption of such practices, little is known about the subsequent implementation and abandonment. We conducted an online survey (n=902) examining the adoption and abandonment of 30 commonly recommended practices. Security practices were more widely adopted than privacy and identity theft protection practices. Manual and fully automatic practices were more widely adopted than practices requiring recurring user interaction. Participants' gender, education, technical background, and prior negative experience are correlated with their levels of adoption. Furthermore, practices were abandoned when they were perceived as low-value, inconvenient, or when users overrode them with subjective judgment. We discuss how security, privacy, and identity theft protection recommendations and tools can be better aligned with user needs.

Introducing Gamettes: A Playful Approach for Capturing Decision-Making for Informing Behavioral Models

Agent-based simulations are widely used for modeling human behavior in various contexts. However, such simulations may oversimplify human decision-making. We propose the use of Gamettes to extract rich data on human decision-making and help in improving the human behavioral aspects of models underlying agent-based simulations. We show how Gamettes are designed and provide empirical validation for using Gamettes in an experimental supply chain setting to study human decision-making. Our results show that Gamettes are successful in capturing the expected behaviors and patterns in supply chain decisions, and, thus, we find evidence for the capability of Gamettes to inform behavioral models.

Others' Images: Online Social Media, Architectural Improvisations, and Spatial Marginalization in Bangladesh

This paper joins the growing body of work in postcolonial computing in HCI, and critically examines the impacts of online social media on the urban architecture in the Global South. Based on our nine-month long ethnography at eight residential areas in Dhaka, Bangladesh, this paper reports how online fame drives local users to produce digital images of their houses mimicking various Western standards, which in turn, brings changes to the organization, aesthetics, and functions of domestic spaces. This paper also describes how such digital image mediated transformations to local architecture are diminishing traditional spaces, altering their usual functions, and limiting the movement of many women inside their home. Drawing from a rich body of literature in postcolonialism, critical image theory, architecture, and Islamic feminism, we explain how these practices demonstrate a subaltern experience of using social media in the Global South. We further discuss design implications to both HCI and architecture to address these issues, and connect our findings to the broader agendas of HCI around social justice and global development.

Being (In)Visible: Privacy, Transparency, and Disclosure in the Self-Management of Bipolar Disorder

Research in personal informatics (PI) calls for systems to sup- port social forms of tracking, raising questions about how privacy can and should support intentionally sharing sensitive health information. We focus on the case of personal data related to the self-tracking of bipolar disorder (BD) in order to explore the ways in which disclosure activities intersect with other privacy experiences. While research in HCI of- ten discusses privacy as a disclosure activity, this does not reflect the ways in which privacy can be passively experienced. In this paper we broaden conceptions of privacy by defining transparency experiences and contributing factors in contrast to disclosure activities and preferences. Next, we ground this theoretical move in empirical analysis of personal narratives shared by people managing BD. We discuss the resulting emer- gent model of transparency in terms of implications for the design of socially-enabled PI systems. CAUTION: This paper contains references to experiences of mental illness, including self-harm, depression, suicidal ideation, etc.

Walking by Cycling: A Novel In-Place Locomotion User Interface for Seated Virtual Reality Experiences

We introduce VR Strider, a novel locomotion user interface (LUI) for seated virtual reality (VR) experiences, which maps cycling biomechanics of the user's legs to virtual walking movements. The core idea is to translate the motion of pedaling on a mini exercise bike to a corresponding walking animation of a virtual avatar while providing audio-based tactile feedback on virtual ground contacts. We conducted an experiment to evaluate the LUI and our novel anchor-turning rotation control method regarding task performance, spatial cognition, VR sickness, sense of presence, usability and comfort in a path-integration task. The results show that VR Strider has a significant positive effect on the participants' angular and distance estimation, sense of presence and feeling of comfort compared to other established locomotion techniques, such as teleportation and joystick-based navigation. A confirmatory study further indicates the necessity of synchronized avatar animations for virtual vehicles that rely on pedalling.

Does Context in Privacy Communication Really Matter? — A Survey on Consumer Concerns and Preferences

Privacy policies as a means of communicating with customers still prove ineffective. Researchers have recently suggested that a specific usage context should be considered to make privacy notices more relevant to users. To explore this approach further, we conducted an explorative online survey of privacy concerns and privacy information preferences with 642 participants for two different contexts (loyalty cards and fitness tracking). Our data shows some support for the suggestion that context may be a significant moderator of concerns and preferences. However, the corresponding effects are rather small and limited to specific concerns and information categories. In line with other research, the data supports the known hierarchy of concerns regarding unauthorized secondary use and improper data access, which seem to exceed concerns about erroneous data processing or excessive data collection in both contexts. Furthermore, participants considered information on personal rights and processing purposes more relevant than information on contact persons.

Senorita: A Chorded Keyboard for Sighted, Low Vision, and Blind Mobile Users

Senorita is a novel two-thumb virtual chorded keyboard for mobile devices. It arranges the letters on eight keys in a single row by the bottom edge of the device based on letter frequencies and the anatomy of the thumbs. Unlike most chorded methods, it provides visual cues to perform the chording actions in sequence, instead of simultaneously, when the actions are unknown, facilitating "learning by doing". Its compact design leaves most of the screen available and its position near the edge accommodates eyes-free text entry. In a longitudinal study with a smartphone, Senorita yielded on average 14 wpm. In a short-term study with a tablet, it yielded on average 9.3 wpm. In the final longitudinal study, it yielded 3.7 wpm with blind users, surpassing their Qwerty performance. Low vision users yielded 5.8 wpm. Further, almost all users found Senorita effective, easy to learn, and wanted to keep use it.

The Role of Everyday Sounds in Advanced Dementia Care

The representation of sounds derived from everyday life can be beneficial for people with dementia by evoking memories and emotional responses. Despite this potential, integrating sound and sound-based interventions in care facilities has not received much research attention. In this paper, we present the findings from a field study that explored the responses of 19 people with advanced dementia to a selection of everyday sounds presented to them in a care home and the role of these responses in the care environment. To study this, we deployed Vita, a 'pillow-like' sound player, in two dementia care facilities for four weeks, during which observations were recorded. Afterwards, we conducted interviews with caregivers who used Vita in everyday care practice. Our findings reveal how everyday sounds provided by Vita stimulated meaningful conversation, playfulness, and connection between residents and caregivers. Furthermore, we propose design implications for integrating everyday sounds in dementia care.

GazeConduits: Calibration-Free Cross-Device Collaboration through Gaze and Touch

We present GazeConduits, a calibration-free ad-hoc mobile interaction concept that enables users to collaboratively interact with tablets, other users, and content in a cross-device setting using gaze and touch input. GazeConduits leverages recently introduced smartphone capabilities to detect facial features and estimate users' gaze directions. To join a collaborative setting, users place one or more tablets onto a shared table and position their phone in the center, which then tracks users present as well as their gaze direction to determine the tablets they look at. We present a series of techniques using GazeConduits for collaborative interaction across mobile devices for content selection and manipulation. Our evaluation with 20 simultaneous tablets on a table shows that GazeConduits can reliably identify which tablet or collaborator a user is looking at.

Leveraging Error Correction in Voice-based Text Entry by Talk-and-Gaze

We present the design and evaluation of Talk-and-Gaze (TaG), a method for selecting and correcting errors with voice and gaze. TaG uses eye gaze to overcome the inability of voice-only systems to provide spatial information. The user's point of gaze is used to select an erroneous word either by dwelling on the word for 800 ms (D-TaG) or by uttering a "select" voice command (V-TaG). A user study with 12 participants compared D-TaG, V-TaG, and a voice-only method for selecting and correcting words. Corrections were performed more than 20% faster with D-TaG compared to the V-TaG or voice-only methods. As well, D-TaG was observed to require 24% less selection effort than V-TaG and 11% less selection effort than voice-only error correction. D-TaG was well received in a subjective assessment with 66% of users choosing it as their preferred choice for error correction in voice-based text entry.

Considerations for Implementing Technology to Support Community Radio in Rural Communities

Rural communities often lack platforms to support civic engagement and local deliberation. Community radio is intended to facilitate such functions, yet, radio technologies can be expensive and complex to use. To tackle this challenge, low-barrier radio technologies are becoming available. We argue that technology to support civic engagement and local deliberation are important, and design of such platforms must take into consideration specific community needs. We contribute by exploring the needs of three rural European communities. Findings indicate that communities are now distributed beyond place. Platforms for deliberation must include both hyper-local and geographically dispersed populations. Rural values of accountability, reliability and maintaining social harmony are important design considerations. Community radio platforms should support geographically distributed community connections, sharing of health and emergency information, preservation of heritage and as a space for advocacy and civic action.

Towards More Universal Wayfinding Technologies: Navigation Preferences Across Disabilities

Accessibility researchers have been studying wayfinding technologies for people with disabilities for decades, typically focusing on solutions within disability populations - for example, technologies to support blind navigation. Yet, we know little about wayfinding needs across disabilities. In this paper, we describe a qualitative interview study examining the urban navigational experiences of 27 people who identified as older adults and/or who had cognitive, visual, hearing, and/or mobility disabilities. We found that many navigation route preferences were shared across disabilities (e.g., desire to avoid carpeted areas), while others diverged or were in tension (e.g., the need to avoid noisy areas while staying near main thoroughfares). To support design for multiple disability groups, we identify four dimensions of navigation preferences - technology, route, assistance, experience - and describe how these might usefully inform design of more universally usable wayfinding technologies.

Reflexive VR Storytelling Design Beyond Immersion: Facilitating Self-Reflection on Death and Loneliness

This research examines the reflexive dimensions of cinematic virtual reality (CVR) storytelling. We created Anonymous, an interactive CVR piece that employs a reflexive storytelling method. This method is based on distancing effects and is used to elicit audience awareness and self-reflection about loneliness and death. To understand the audience's experiences, we conducted in-depth interviews to study which design factors and elements prompted reflexive thoughts and feelings. Our findings highlight how the audience experience was impacted by four reflexive dimensions: abstract and minimal aesthetics, everyday materials and textures, the restriction of control, and multiple, disembodied points of view. We use our findings to discuss how these dimensions can inform the design of VR storytelling experiences that provoke self and social reflection.

Awareness, Navigation, and Use of Feed Control Settings Online

Control settings are abundant and have significant effects on user experiences. One example of an impactful but understudied area is feed settings. In this study, we investigated awareness, navigation, and use of feed settings. We began by creating a taxonomy of feed settings on social media and search sites. Via an online survey, we measured awareness of Facebook feed settings. An in-person interview study then investigated how people navigated to and chose to set feed settings on their own feeds. We discovered that many participants did not believe ad personalization feed settings existed. Furthermore, we discovered a misalignment in the expectation and the function of settings, especially of ad personalization settings for many participants. Despite all participants struggling to find at least one setting, participants overall wanted to use settings: 94% altered at least one setting they encountered. From these results, we discuss implications and suggest design guidelines for settings.

SleepBandits: Guided Flexible Self-Experiments for Sleep

Self-experiments allow people to explore what behavioral changes lead to improved health and wellness. However, it is challenging to run such experiments in a scientifically valid way that is also flexible and able to accommodate the realities of daily life. We present a set of design principles for guided self-experiments that aim to lower this barrier to self-experimentation. We demonstrate the value of the principles by implementing them in SleepBandits, an integrated system that includes a smartphone application for sleep experiments. SleepBandits guides users through the steps of a single-case experiment, automatically collecting data from the built-in sensors and user input and calculating and presenting results in real-time. We released SleepBandits to the Google Play Store and people voluntarily downloaded and used it. Based on the data from 365 active users from this in-the-wild study, we discuss opportunities and challenges with the design principles and the SleepBandits system.

I'm All Eyes and Ears: Exploring Effective Locators for Privacy Awareness in IoT Scenarios

With the proliferation of IoT devices, there are growing concerns about being sensed or monitored by these devices unawares, especially in places perceived as private. We explore the design space of IoT locators to help people physically find nearby IoT devices. We first conducted a survey to understand people's willingness, current practices, and challenges in finding IoT devices. Our survey findings motivated us to design and implement low-cost locators (visual, auditory, and contextualized pictures) to help people find nearby devices. Through an iterative design process and two rounds of experiments, we found that these locators greatly reduced people's search time over a baseline of no locators. Many participants found the visual and auditory locators enjoyable. Some participants also appropriated the use of our system for other purposes, e.g., to learn about new IoT devices, instead of for privacy awareness.

Is Your Time Well Spent? Reflecting on Knowledge Work More Holistically

The modern workplace is more demanding than ever before. Yet, since the industrial age, productivity measures have predominantly stayed narrowly focused on the output of the work, and not accounted for the big shift in the cognitive demands placed on the workers or the interleaving of work and life that is so common today. We posit that a more holistic conceptualization of Time Well Spent (TWS) at work could mitigate this issue. In our 1-week study, 40 knowledge workers used the experience sampling method (ESM) to rate their TWS and then define TWS at the end of the week. Our work contributes a preliminary characterization of TWS and empirical evidence that this term can capture a more holistic notion of work that also includes the worker's feelings and well-being.

Attenuated Access: Accounting for Startup, Maintenance, and Affective Costs in Resource-Constrained Communities

The term "digital divide" indexes a body of research at the intersection of digital technology and social equity, including research on inequality that criticizes and recapitulates the original concept. Based on a qualitative study at a community literacy center serving resettled refugees and immigrants, we show that the digital divide framework rests on a distributive logic, one that implies that distributing access to digital technology constitutes a form of social equity. Because this framework only considers valorized goods, skills, and uses, research has frequently ignored the startup, maintenance, and affective costs we found accompanied digital access for our participants. To account for these costs, we propose a theoretical adjustment to the digital divide framework, one where design is an act of configuring both costs and benefits together. We argue that considering such costs enables HCI researchers to engage more effectively with host communities in the non-innocent work of confronting inequity.

A Rapid Tapping Task on Commodity Smartphones to Assess Motor Fatigability

Fatigue is a common debilitating symptom of many autoimmune diseases, including multiple sclerosis. It negatively impacts patients' every-day life and productivity. Despite its prevalence, fatigue is still poorly understood. Its subjective nature makes quantification challenging and it is mainly assessed by questionnaires, which capture the magnitude of fatigue insufficiently. Motor fatigability, the objective decline of performance during a motor task, is an underrated aspect in this regard. Currently, motor fatigability is assessed using a handgrip dynamometer. This approach has been proven valid and accurate but requires special equipment and trained personnel. We propose a technique to objectively quantify motor fatigability using a commodity smartphone. The method comprises a simple exertion task requiring rapid alternating tapping. Our study with 20 multiple sclerosis patients and 35 healthy participants showed a correlation of rho = 0.8 with the baseline handgrip method. This smartphone-based approach is a first step towards ubiquitous, more frequent, and remote monitoring of fatigability and disease progression.

Optimizing User Interface Layouts via Gradient Descent

Automating parts of the user interface (UI) design process has been a longstanding challenge. We present an automated technique for optimizing the layouts of mobile UIs. Our method uses gradient descent on a neural network model of task performance with respect to the model's inputs to make layout modifications that result in improved predicted error rates and task completion times. We start by extending prior work on neural network based performance prediction to 2-dimensional mobile UIs with an expanded interaction space. We then apply our method to two UIs, including one that the model had not been trained on, to discover layout alternatives with significantly improved predicted performance. Finally, we confirm these predictions experimentally, showing improvements up to 9.2 percent in the optimized layouts. This demonstrates the algorithm's efficacy in improving the task performance of a layout, and its ability to generalize and improve layouts of new interfaces.

Questioning the AI: Informing Design Practices for Explainable AI User Experiences

A surge of interest in explainable AI (XAI) has led to a vast collection of algorithmic work on the topic. While many recognize the necessity to incorporate explainability features in AI systems, how to address real-world user needs for understanding AI remains an open question. By interviewing 20 UX and design practitioners working on various AI products, we seek to identify gaps between the current XAI algorithmic work and practices to create explainable AI products. To do so, we develop an algorithm-informed XAI question bank in which user needs for explainability are represented as prototypical questions users might ask about the AI, and use it as a study probe. Our work contributes insights into the design space of XAI, informs efforts to support design practices in this space, and identifies opportunities for future XAI work. We also provide an extended XAI question bank and discuss how it can be used for creating user-centered XAI.

The Emerging Professional Practice of Remote Sighted Assistance for People with Visual Impairments

People with visual impairments (PVI) must interact with a world they cannot see. Remote sighted assistance (RSA) has emerged as a conversational assistive technology. We interviewed RSA assistants ("agents") who provide assistance to PVI via a conversational prosthetic called Aira ( to understand their professional practice. We identified four types of support provided: scene description, navigation, task performance, and social engagement. We discovered that RSA provides an opportunity for PVI to appropriate the system as a richer conversational/social support tool. We studied and identified patterns in how agents provide assistance and how they interact with PVI as well as the challenges and strategies associated with each context. We found that conversational interaction is highly context-dependent. We also discuss implications for design.

Understanding Viewport- and World-based Pointing with Everyday Smart Devices in Immersive Augmented Reality

Personal smart devices have demonstrated a variety of efficient techniques for pointing and selecting on physical displays. However, when migrating these input techniques to augmented reality, it is both unclear what the relative performance of different techniques will be given the immersive nature of the environment, and it is unclear how viewport-based versus world-based pointing methods will impact performance. To better understand the impact of device and viewing perspectives on pointing in augmented reality, we present the results of two controlled experiments comparing pointing conditions that leverage various smartphone- and smartwatch-based external display pointing techniques and examine viewport-based versus world-based target acquisition paradigms. Our results demonstrate that viewport-based techniques offer faster selection and that both smartwatch- and smartphone-based pointing techniques represent high-performance options for performing distant target acquisition tasks in augmented reality.

Scout: Rapid Exploration of Interface Layout Alternatives through High-Level Design Constraints

Although exploring alternatives is fundamental to creating better interface designs, current processes for creating alternatives are generally manual, limiting the alternatives a designer can explore. We present Scout, a system that helps designers rapidly explore alternatives through mixed-initiative interaction with high-level constraints and design feedback. Prior constraint-based layout systems use low-level spatial constraints and generally produce a single design. Tosupport designer exploration of alternatives, Scout introduces high-level constraints based on design concepts (e.g.,~semantic structure, emphasis, order) and formalizes them into low-level spatial constraints that a solver uses to generate potential layouts. In an evaluation with 18 interface designers, we found that Scout: (1) helps designers create more spatially diverse layouts with similar quality to those created with a baseline tool and (2) can help designers avoid a linear design process and quickly ideate layouts they do not believe they would have thought of on their own.

Prehabilitation: Care Challenges and Technological Opportunities

Millions of surgeries are performed in the US annually, and numbers are trending upwards. Traditional rehabilitative interventions are struggling to meet current demands, and researchers have turned to pre-operative interventions, or prehabilitation, to improve patient functions. However, existing literature primarily discusses efficacy or the use of commercial sensing devices, and lacks a clear comprehension of healthcare professionals' (HPs') needs and perspectives. User-centered stakeholder understandings are crucial for a technology's adoption, but prehabilitation literature lacks such understandings. Therefore we conduct semi-structured interviews with 12 prehabilitation healthcare professionals (HPs) to offer descriptions of care challenges, tool usage, and perspectives regarding suitable and effective technologies. These data can assist designers in fostering prehabilitation processes via tailored prehabilitation tools which meet HPs' needs and expectations.

"You Don't Have To Know My Past": How WeChat Moments Users Manage Their Evolving Self-Presentation

Most social media platforms record, display, and archive users' personal histories. This persistence of posts over time can be problematic, as users' self-presentation goals and network composition change, but old content remains. In this paper, we explore an alternative feature that provides control over content persistence. We present findings from interviews with 16 users of the popular Chinese social media platform WeChat Moments. We focused on Moments' Time Limit setting, which makes social media data ephemeral to audiences, but persistent to posters. Interviewees described changes in their self-presentation goals and social network composition over time and reported the Time Limit feature helped them effortlessly manage their desired self-presentation as they matured. Drawing on these findings, we discuss design implications for social media to facilitate greater control over content visibility and persistence, which may have significant benefits for social media users with large and diverse networks.

Affect Recognition using Psychophysiological Correlates in High Intensity VR Exergaming

User experience estimation of VR exergame players by recognising their affective state could enable us to personalise and optimise their experience. Affect recognition based on psychophysiological measurements has been successful for moderate intensity activities. High intensity VR exergames pose challenges as the effects of exercise and VR headsets interfere with those measurements. We present two experiments that investigate the use of different sensors for affect recognition in a VR exergame. The first experiment compares the impact of physical exertion and gamification on psychophysiological measurements during rest, conventional exercise, VR exergaming, and sedentary VR gaming. The second experiment compares underwhelming, overwhelming and optimal VR exergaming scenarios. We identify gaze fixations, eye blinks, pupil diameter and skin conductivity as psychophysiological measures suitable for affect recognition in VR exergaming and analyse their utility in determining affective valence and arousal. Our findings provide guidelines for researchers of affective VR exergames.

Computational Alternatives Vignettes for Place- and Activity-Centered Digital Services in Public Libraries

We investigate how to design community technologies for public events. We do so with a focus on technologies that give rise to new forms of participation and knowledge co-production in public libraries. Specifically, we deployed a digital service at a major public library during its four-week creative workshop series. The system offered an alternative way for people to work together as a community, to go beyond achieving individual goals, and to contribute to the achievement of public goals (e.g., building community bookshelves). We report on how the system has reconfigured physical spaces and afforded new social practices in the library. We propose Computational Alternatives as a fruitful approach for gaining situated, nuanced insights into a technology's possible adoption. We offer key insights in the form of computational alternatives vignettes -- grounded stories that encapsulate sociotechnical implications of technology, pointing to plausible alternative futures.

"And This, Kids, Is How I Met Your Mother": Consumerist, Mundane, and Uncanny Futures with Sex Robots

Sex Robots are no longer science fiction and may soon be-come widespread. While much discussion has developed in academia on their moral and social impact, sex robots have yet to be examined from a critical design perspective and are under-explored in HCI. We use the Story Completion Method(SCM) to explore commonplace assumptions around futures with sex robots and discuss those from a critical design perspective. Thirty five participants completed a story stem of a human encountering a sex robot or vice-versa. Through thematic analysis, we show narratives of consumerist relation-ships between humans and sex robots, stories that describe sex robots as highly-efficient sex workers that (out)perform humans in routinal sex activities, and narratives that explore sex robots as empathetic and sentient beings. Our participant-created stories both reinforce and challenge established norms of sex robots and raise questions that concern responsible design and ethics in HCI. Finally, we show opportunities and limitations of using multiple-perspective story stems in SCM

Neo-Noumena: Augmenting Emotion Communication

The subjective experience of emotion is notoriously difficult to interpersonally communicate. We believe that technology can challenge this notion through the design of neuroresponsive systems for interpersonal communication. We explore this through "Neo-Noumena", a communicative neuroresponsive system that uses brain-computer interfacing and artificial intelligence to read one's emotional states and dynamically represent them to others in mixed reality through two head-mounted displays. In our study five participant pairs were given Neo-Noumena for three days, using the system freely. Measures of emotional competence demonstrated a statistically significant increase in participants' ability to interpersonally regulate emotions. Furthermore, participant interviews revealed themes regarding Spatiotemporal Actualization, Objective Representation, and Preternatural Transmission. We also suggest design strategies for future augmented emotion communication systems. We intend that work gives guidance towards a future in which our ability to interpersonally communicate emotion is augmented beyond traditional experience.

UI Dark Patterns and Where to Find Them: A Study on Mobile Applications and User Perception

A Dark Pattern (DP) is an interface maliciously crafted to deceive users into performing actions they did not mean to do. In this work, we analyze Dark Patterns in 240 popular mobile apps and conduct an online experiment with 589 users on how they perceive Dark Patterns in such apps. The results of the analysis show that 95% of the analyzed apps contain one or more forms of Dark Patterns and, on average, popular applications include at least seven different types of deceiving interfaces. The online experiment shows that most users do not recognize Dark Patterns, but can perform better in recognizing malicious designs if informed on the issue. We discuss the impact of our work and what measures could be applied to alleviate the issue.

Closer Object Looks Smaller: Investigating the Duality of Size Perception in a Spherical Fish Tank VR Display

Fish Tank Virtual Reality (FTVR) displays provide compelling 3D experiences by rendering view-dependent imagery on a 2D screen. While users perceive a 3D object in space, they are actually looking at pixels on a 2D screen, thus, a perceptual duality exists between the object's pixels and the 3D percept potentially interfering with the experience. To investigate, we conducted an experiment to see whether the on-screen size of the 2D imagery affects the perceived object size in 3D space with different viewing conditions, including stereopsis. We found that the size of on-screen imagery significantly influenced object size perception, causing 83.3% under/overestimation of perceived size when viewing without stereopsis and reducing to 64.7% with stereopsis. Contrary to reality, objects look smaller when the viewer gets closer. Understanding the perceptual duality helps us to provide accurate perception of real-world objects depicted in the virtual environment and pave the way for 3D applications.

Relationship Between Visual Complexity and Aesthetics of Webpages

Substantial HCI research investigated the relationship between webpage complexity and aesthetics, but without a definitive conclusion. Some research showed an inverse linear correlation, some other showed an inverted u-shaped curve, while the rest showed no relationship at all. Such a lack of clarity complicates hypothesis formulation and result interpretation for future research, and lowers the reliability and generalizability of potential advice for Web design practice. We re-collected complexity and aesthetics ratings for five datasets previously used in webpage aesthetics and complexity research. The results were mixed, but suggested an inverse linear relationship with a weaker u-shaped sub-component. A subsequent visual inspection of revealed several confounding factors that may have led to the mixed results, including some webpages looking broken or archaic. The second data collection showed that accounting for these factors generally eliminates the u-shaped tendency of the complexity-aesthetics relationship, at least, for a relatively homogeneous sample of English-speaking participants.

Join.Love: A Sociotechnical Genealogy of the Legalization of Same-Sex Marriage

HCI researchers interested in enhancing democracy have introduced methods and technologies that support democratic political processes, such as voting, and more broadly on empowering people to more fully participate in an increasingly technologized world. The aspiration for technologies to support meaningful democratic outcomes is not misplaced. In 2019, headlines around the world announced that Taiwan had become the first Asian country to legalize same-sex marriage, an impressive political achievement. But it was also an impressive technical achievement, the outcome of a concerted effort to develop responsive and impactful direct democracy platforms. We offer a sociotechnical genealogy of the process, informed by theory of deliberative democracy. We identify three opportunities for future HCI contributions: supporting less visible consensus-es, developing civic journeys, and engaging in deliberative experience design.

Who Put That There? Temporal Navigation of Spatial Recordings by Direct Manipulation

Spatial recordings allow viewers to move within them and freely choose their viewpoint. However, such recordings make it easy to miss events and difficult to follow moving objects when skipping through the recording. To alleviate these problems we present the Who Put That There system that allows users to navigate through time by directly manipulating objects in the scene. By selecting an object, the user can navigate to moments where the object changed. Users can also view trajectories of objects that changed location and directly manipulate them to navigate. We evaluated the system with a set of sensemaking questions in a think-aloud study. Participants understood the system and found it useful for finding events of interest, while being present and engaged in the recording.

"We Hold Each Other Accountable": Unpacking How Social Groups Approach Cybersecurity and Privacy Together

Digital resources are often collectively owned and shared by small social groups (e.g., friends sharing Netflix accounts, roommates sharing game consoles, families sharing WhatsApp groups). Yet, little is known about (i) how these groups jointly navigate cybersecurity and privacy (S&P) decisions for shared resources, (ii) how shared experiences influence individual S&P attitudes and behaviors, and (iii) how well existing S&P controls map onto group needs. We conducted group interviews and a supplemental diary study with nine social groups (n=34) of varying relationship types. We identified why, how and what resources groups shared, their jointly construed threat models, and how these factors influenced group strategies for securing shared resources. We also identified missed opportunities for cooperation and stewardship among group members that could have led to improved S&P behaviors, and found that existing S&P controls often fail to meet the needs of these small social groups.

"How do I make this thing smile?": An Inventory of Expressive Nonverbal Communication in Commercial Social Virtual Reality Platforms

Despite the proliferation of platforms for social Virtual Reality (VR) communicating emotional expression via an avatar remains a significant design challenge. In order to better understand the design space for expressive Nonverbal Communication (NVC) in social VR we undertook an inventory of the ten most prominent social VR platforms. Our inventory identifies the dominant design strategies for movement, facial control, and gesture in commercial VR applications, and identifies opportunities and challenges for future design and research into social expression in VR. Specifically, we highlight the paucity of interaction paradigms for facial expression and the near nonexistence of meaningful control over ambient aspects of nonverbal communication such as posture, pose, and social status.

"You Cannot Offer Such a Suggestion": Designing for Family Caregiver Input in Home Care Systems

Previous work has looked closely at the challenges of using patient-generated data to enable remote assessment and monitoring by healthcare professionals. In this paper, we examine family caregivers who act as proxies for patients who may not have the capacity of capturing the necessary data. We worked with occupational therapists to develop an application for remote assessment of the safety of patients' homes by occupational therapists with the assistance of family caregivers. We evaluated the application with family caregivers and found two features unique to communication between family caregivers and healthcare professionals: Caregivers want to be able to direct healthcare professionals' attention to support problem-solving at home, and they include their perspective on how to best meet the patient's health needs. We discuss the importance of these findings for home systems in the domain of long-term chronic care.

Scenario Co-Creation Cards: A Culturally Sensitive Tool for Eliciting Values

Values are an integral part of human identity and have a pervasive impact upon human behavior. This makes understanding them a central concern in the design of technology, as exemplified by approaches such as Value Sensitive Design ("VSD"). Identifying and concreting the values held by a given population can be a difficult endeavor, especially where there is a cultural barrier limiting an effective discussion of them, for example in societies where freedom of expression is discouraged. Addressing this concern requires an in-depth consideration of appropriate value elicitation methods, which responds to the fact that it is not possible to understand values detached from their cultural context. We introduce a novel implicit method, Scenario Co-Creation Cards, and show how it can be used to incorporate existing models of culture in the value elicitation process. We demonstrate this in a case study of Saudi women's visibility in the digital media.

SolutionChat: Real-time Moderator Support for Chat-based Structured Discussion

Online chat is an emerging channel for discussing community problems. It is common practice for communities to assign dedicated moderators to maintain a structured discussion and enhance the problem-solving experience. However, due to the synchronous nature of online chat, moderators face a high managerial overhead in tasks like discussion stage management, opinion summarization, and consensus-building support. To assist moderators with facilitating a structured discussion for community problem-solving, we introduce SolutionChat, a system that (1) visualizes discussion stages and featured opinions and (2) recommends contextually appropriate moderator messages. Results from a controlled lab study (n=55, 12 groups) suggest that participants' perceived discussion trackability was significantly higher with SolutionChat than without. Also, moderators provided better summarization with less effort and better managerial support using system-generated messages with SolutionChat than without. With SolutionChat, we envision untrained moderators to effectively facilitate chat-based discussions of important community matters.

ORCSolver: An Efficient Solver for Adaptive GUI Layout with OR-Constraints

OR-constrained (ORC) graphical user interface layouts unify conventional constraint-based layouts with flow layouts, which enables the definition of flexible layouts that adapt to screens with different sizes, orientations, or aspect ratios with only a single layout specification. Unfortunately, solving ORC layouts with current solvers is time-consuming and the needed time increases exponentially with the number of widgets and constraints. To address this challenge, we propose ORCSolver, a novel solving technique for adaptive ORC layouts, based on a branch-and-bound approach with heuristic preprocessing. We demonstrate that ORCSolver simplifies ORC specifications at runtime and our approach can solve ORC layout specifications efficiently at near-interactive rates.

'Lime', 'Open Lock', and 'Blocked': Children's Perception of Colors, Symbols, and Words in Cybersecurity Warnings

Cybersecurity warnings are frequently ignored or misinterpreted by even experienced adults. While studies have been conducted to examine warning design for adults, there is little data to establish recommendations for children. We conducted user studies with 22 children (ages 10-12) and with 22 adults. We compare their risk perception of warning design parameters (signal colors, symbols, words) via card sorting and ranking activities followed by interviews. While our findings suggest similarities in how both groups interpret the design parameters (e.g., red, skull, and fatal convey danger), we also uncovered potential concerns with items currently used as security indicators (e.g., both groups had mixed interpretations of the open lock and police officer symbols). Individual risk perception, particularly for children, appears dependent on personal preferences and experience. Our findings suggest implications and future research directions for the design of cybersecurity warnings for children.

The Government's Dividend: Complex Perceptions of Social Media Misinformation in China

The social media environment in China has become the dominant source of information and news over the past decade. This news environment has naturally suffered from challenges related to mis- and dis-information, encumbered by an increasingly complex landscape of factors and players including social media services, fact-checkers, censorship policies, and astroturfing. Interviews with 44 Chinese WeChat users were conducted to understand how individuals perceive misinformation and how it impacts their news consumption practices. Overall, this work exposes the diverse attitudes and coping strategies that Chinese users employ in complex social media environments. Due to the complex nature of censorship in China and participants' lack of understanding of censor-ship, they expressed varied opinions about its influence on the credibility of online information sources. Further, although most participants claimed that their opinions would not be easily swayed by astroturfers, many admitted that they could not effectively distinguish astroturfers from ordinary Internet users. Participants' inability to make sense of comments found online lead many participants to hold pro-censorship attitudes: the Government's Dividend.

Embodied Axes: Tangible, Actuated Interaction for 3D Augmented Reality Data Spaces

We present Embodied Axes, a controller which supports selection operations for 3D imagery and data visualisations in Augmented Reality. The device is an embodied representation of a 3D data space -- each of its three orthogonal arms corresponds to a data axis or domain specific frame of reference. Each axis is composed of a pair of tangible, actuated range sliders for precise data selection, and rotary encoding knobs for additional parameter tuning or menu navigation. The motor actuated sliders support alignment to positions of significant values within the data, or coordination with other input: e.g., mid-air gestures in the data space, touch gestures on the surface below the data, or another Embodied Axes device supporting multi-user scenarios. We conducted expert enquiries in medical imaging which provided formative feedback on domain tasks and refinements to the design. Additionally, a controlled user study was performed and found that the Embodied Axes was overall more accurate than conventional tracked controllers for selection tasks.

ARchitect: Building Interactive Virtual Experiences from Physical Affordances by Bringing Human-in-the-Loop

Automatic generation of Virtual Reality (VR) worlds which adapt to physical environments have been proposed to enable safe walking in VR. However, such techniques mainly focus on the avoidance of physical objects as obstacles and overlook their interaction affordances as passive haptics. Current VR experiences involving interaction with physical objects in surroundings still require verbal instruction from an assisting partner. We present ARchitect, a proof-of-concept prototype that allows flexible customization of a VR experience with human-in-the-loop. ARchitect brings in an assistant to map physical objects to virtual proxies of matching affordances using Augmented Reality (AR). In a within-subjects study (9 user pairs) comparing ARchitect to a baseline condition, assistants and players experienced decreased workload and players showed increased VR presence and trust in the assistant. Finally, we defined design guidelines of ARchitect for future designers and implemented three demonstrative experiences.

COGAM: Measuring and Moderating Cognitive Load in Machine Learning Model Explanations

Interpretable machine learning models trade -off accuracy for simplicity to make explanations more readable and easier to comprehend. Drawing from cognitive psychology theories in graph comprehension, we formalize readability as visual cognitive chunks to measure and moderate the cognitive load in explanation visualizations. We present Cognitive-GAM (COGAM) to generate explanations with desired cognitive load and accuracy by combining the expressive nonlinear generalized additive models (GAM) with simpler sparse linear models. We calibrated visual cognitive chunks with reading time in a user study, characterized the trade-off between cognitive load and accuracy for four datasets in simulation studies, and evaluated COGAM against baselines with users. We found that COGAM can decrease cognitive load without decreasing accuracy and/or increase accuracy without increasing cognitive load. Our framework and empirical measurement instruments for cognitive load will enable more rigorous assessment of the human interpretability of explainable AI.

TandemTrack: Shaping Consistent Exercise Experience by Complementing a Mobile App with a Smart Speaker

Smart speakers such as Amazon Echo present promising opportunities for exploring voice interaction in the domain of in-home exercise tracking. In this work, we examine if and how voice interaction complements and augments a mobile app in promoting consistent exercise. We designed and developed TandemTrack, which combines a mobile app and an Alexa skill to support exercise regimen, data capture, feedback, and reminder. We then conducted a four-week between-subjects study deploying TandemTrack to 22 participants who were instructed to follow a short daily exercise regimen: one group used only the mobile app and the other group used both the app and the skill. We collected rich data on individuals' exercise adherence and performance, and their use of voice and visual interactions, while examining how TandemTrack as a whole influenced their exercise experience. Reflecting on these data, we discuss the benefits and challenges of incorporating voice interaction to assist daily exercise, and implications for designing effective multimodal systems to support self-tracking and promote consistent exercise.

CurveBoards: Integrating Breadboards into Physical Objects to Prototype Function in the Context of Form

CurveBoards are breadboards integrated into physical objects. In contrast to traditional breadboards, CurveBoards better preserve the object's look and feel while maintaining high circuit fluidity, which enables designers to exchange and reposition components during design iteration. Since CurveBoards are fully functional, i.e., the screens are displaying content and the buttons take user input, designers can test interactive scenarios and log interaction data on the physical prototype while still being able to make changes to the component layout and circuit design as needed. We present an interactive editor that enables users to convert 3D models into CurveBoards and discuss our fabrication technique for making CurveBoard prototypes. We also provide a technical evaluation of CurveBoard's conductivity and durability and summarize informal user feedback.

ICONATE: Automatic Compound Icon Generation and Ideation

Compound icons are prevalent on signs, webpages, and infographics, effectively conveying complex and abstract concepts, such as "no smoking" and "health insurance", with simple graphical representations. However, designing such icons requires experience and creativity, in order to efficiently navigate the semantics, space, and style features of icons. In this paper, we aim to automate the process of generating icons given compound concepts, to facilitate rapid compound icon creation and ideation. Informed by ethnographic interviews with professional icon designers, we have developed ICONATE, a novel system that automatically generates compound icons based on textual queries and allows users to explore and customize the generated icons. At the core of ICONATE is a computational pipeline that automatically finds commonly used icons for sub-concepts and arranges them according to inferred conventions. To enable the pipeline, we collected a new dataset, Compicon1k, consisting of 1000 compound icons annotated with semantic labels (i.e., concepts). Through user studies, we have demonstrated that our tool is able to automate or accelerate the compound icon design process for both novices and professionals.

Body-Penetrating Tactile Phantom Sensations

In tactile interaction, a phantom sensation refers to an illusion felt on the skin between two distant points at which vibrations are applied. It can improve the perceptual spatial resolution of tactile stimulation with a few tactors. All phantom sensations reported in the literature act on the skin or out of the body, but no such reports exist for those eliciting sensations penetrating the body. This paper addresses tactile phantom sensations in which two vibration actuators on the dorsal and palmar sides of the hand present an illusion of vibration passing through the hand. We also demonstrate similar tactile illusions for the torso. For optimal design, we conducted user studies while varying vibration frequency, envelope function, stimulus duration, and penetrating direction. Based on the results, we present design guidelines on penetrating phantom sensations for its use in immersive virtual reality applications.

Sensitizing Scenarios: Sensitizing Designer Teams to Theory

Concepts and theories that emerge within the social sciences tend to be nuanced, dealing with complex social phenomena. While their relevance to design could be high, it is difficult to make sense of them in design projects, especially when participants have a variety of backgrounds. We report on our experiences using role-play scenarios as a way to sensitize heterogeneous designer teams to complex theoretical concepts related to museology as social and cultural phenomena. We discuss design requirements on such scenarios, and the importance of connecting their execution closely to the context of the design and the current stage of the design process.

Digital Fabrication Tools at Work: Probing Professionals' Current Needs and Desired Futures

Digital fabrication tools have transformed how people work in micro- and small-scale manufacturing settings. While increasing efficiency and precision, these tools raise concerns around user agency and control. This paper describes an exploratory study investigating the felt work experience and desired futures of professionals who use fabrication tools. We conducted co-design workshops with 23 professionals who use 3D printers, laser cutters, and CNC routers. We probed about current practices; machine awareness and autonomy; and user agency. Our findings reveal that current tools are not very professional. They are unreliable and untrustworthy. Participants desired smarter tools that can actively prevent errors and perform self-calibration and self-maintenance. They had few concerns that more intelligence would impact agency. They desired tools that could negotiate trade-offs between time, cost, and quality; and that can operate as super-human shop assistants. We discuss the implications of these findings as opportunities for research that can improve professionals' work experience.

Remotely Shaping the View in Surgical Telementoring

Distributed collaboration on physical tasks is a social process that involves all actors iteratively proposing, assessing and modifying the view of a shared workspace. In this paper, we describe the ways in which a view of a shared workspace is shaped by a remote expert to weave their expertise into the accomplishment of a complex physical task during surgical telementoring. We focus on the communicative functions of talk and actions used by the remote experts and local workers and identify strategies the experts employ to remotely shape the view. This analysis reveals the possibility for collaborative shaping of a view in surgical telementoring as well as other mechanism for a remote expert to craft and present a view of the shared workspace.

Collaborative Aspects of Collecting and Reflecting on Behavioral Data

Direct observation of behavior provides a unique type of data for reflecting on during a process of behavioral intervention. This study focuses on practitioners who specialize in operationalizing, recording, and monitoring behavior using data collection through paper-and-pencil or, increasingly, mobile computing. Applying an action research approach, we conducted fieldwork to understand observational data collection among practitioners providing children with special education support for behavioral needs. We present a model of collaborative data collection, which describes how practices are situated in the process of collecting data that are useful for reflection by teams of practitioners. We discuss how computer-assisted data collection could promote more systematic and rigorous practices, and design considerations for the collaborative aspects of collecting and reflecting on behavioral data. This study builds on research describing the practices of individuals who track their own behavioral data, and improves our understanding of informal documentation practices in organizations.

No Explainability without Accountability: An Empirical Study of Explanations and Feedback in Interactive ML

Automatically generated explanations of how machine learning (ML) models reason can help users understand and accept them. However, explanations can have unintended consequences: promoting over-reliance or undermining trust. This paper investigates how explanations shape users' perceptions of ML models with or without the ability to provide feedback to them: (1) does revealing model flaws increase users' desire to "fix" them; (2) does providing explanations cause users to believe - wrongly - that models are introspective, and will thus improve over time. Through two controlled experiments - varying model quality - we show how the combination of explanations and user feedback impacted perceptions, such as frustration and expectations of model improvement. Explanations without opportunity for feedback were frustrating with a lower quality model, while interactions between explanation and feedback for the higher quality model suggest that detailed feedback should not be requested without explanation. Users expected model correction, regardless of whether they provided feedback or received explanations.

Mirror Ritual: An Affective Interface for Emotional Self-Reflection

This paper introduces a new form of real-time affective interface that engages the user in a process of conceptualisation of their emotional state. Inspired by Barrett's Theory of Constructed Emotion, 'Mirror Ritual' aims to expand upon the user's accessible emotion concepts, and to ultimately provoke emotional reflection and regulation. The interface uses classified emotions – obtained through facial expression recognition -- as a basis for dynamically generating poetry. The perceived emotion is used to seed a poetry generation system based on OpenAI's GPT-2 model, fine-tuned on a specially curated corpus. We evaluate the device's ability to foster a personalised, meaningful experience for individual users over a sustained period. A qualitative analysis revealed that participants were able to affectively engage with the mirror, with each participant developing a unique interpretation of its poetry in the context of their own emotional landscape.

Podoportation: Foot-Based Locomotion in Virtual Reality

Virtual Reality (VR) allows for infinitely large environments. However, the physical traversable space is always limited by real-world boundaries. This discrepancy between physical and virtual dimensions renders traditional locomotion methods used in real world unfeasible. To alleviate these limitations, research proposed various artificial locomotion concepts such as teleportation, treadmills, and redirected walking. However, these concepts occupy the user's hands, require complex hardware or large physical spaces. In this paper, we contribute nine VR locomotion concepts for foot-based locomotion, relying on the 3D position of the user's feet and the pressure applied to the sole as input modalities. We evaluate our concepts and compare them to state-of-the-art point & teleport technique in a controlled experiment with 20 participants. The results confirm the viability of our approaches for foot-based and engaging locomotion. Further, based on the findings, we contribute a wireless hardware prototype implementation.

Relational, Flexible, Everyday: Learning from Ethics in Dementia Research

Engaging in participatory research in HCI raises numerous ethical complexities such as consent, researcher relationships, and participant compensation. Doing HCI work in the area of dementia amplifies these issues, and researchers in this area are modelling ethical stances to ensure researcher-participant relationships focus on meaningful engagement and care. This paper presents an insight into the kinds of ethical foci required when doing design research with people living with dementia and their carers. We interviewed 22 HCI researchers with experience working in dementia care contexts. Our qualitative analysis outlines subsequent lessons-learned, such as recognition of the participants, self-care, research impact, and subjectivity in ethical review boards. Furthermore, we found the complexity of navigating both "everyday" and more formal, institutional ethics in dementia research has implications beyond the context of working with people with dementia and outline key considerations for ethical practices in socially orientated HCI research.

VRSketchIn: Exploring the Design Space of Pen and Tablet Interaction for 3D Sketching in Virtual Reality

Sketching in virtual reality (VR) enhances perception and understanding of 3D volumes, but is currently a challenging task, as spatial input devices (e.g., tracked controllers) do not provide any scaffolding or constraints for mid-air interaction. We present VRSketchIn, a VR sketching application using a 6DoF-tracked pen and a 6DoF-tracked tablet as input devices, combining unconstrained 3D mid-air with constrained 2D surface-based sketching. To explore what possibilities arise from this combination of 2D (pen on tablet) and 3D input (6DoF pen), we present a set of design dimensions and define the design space for 2D and 3D sketching interaction metaphors in VR. We categorize prior art inside our design space and implemented a subset of metaphors for pen and tablet sketching in our prototype. To gain a deeper understanding which specific sketching operations users perform with 2D and which with 3D metaphors, we present findings of usability walkthroughs with six participants.

Conversational Technologies for In-home Learning: Using Co-Design to Understand Children's and Parents' Perspectives

Today, Conversational Agents (CA) are deeply integrated into the daily lives of millions of families, which has led children to extensively interact with such devices. Studies have suggested that the social nature of CA makes them a good learning companion for children. Therefore, to understand children's preferences for the use of CAs for the purpose of in-home learning, we conducted three participatory design sessions. In order to identify parents' requirements in this regard, we also included them in the third session. We found that children expect such devices to possess a personality and an advanced level of intelligence, and support multiple content domains and learning modes and human-like conversations. Parents desire such devices to include them in their children's learning activities, foster social engagement, and to allow them to monitor their children's use. This understanding will inform the design of future CAs for the purpose of in-home learning.

The Burden of Ending Online Account Sharing

Many people share online accounts, even in situations where high privacy and security are expected. Naturally, the sharing of these accounts does not endure forever. This paper reports the privacy and security challenges that people experience when they stop online account sharing. We conducted semi-structured interviews with 25 participants who stopped sharing at least one online account in the 12 months preceding the study. Our results suggest that users experience cognitive and psychosocial burdens when ending account sharing. We offer suggestions for how to improve the design of online accounts to support users better when they end account sharing.

"We can learn. Why not?": Designing Technologies to Engender Equity for Home Health Aides

HCI researchers have increasingly studied how technology might improve the lives of marginalized workers. We explored this question through a qualitative study with home health aides in New York City, a vulnerable group of frontline caregivers whose work with patients is poorly paid and highly stressful, often involving life-or-death situations. To elicit the perspectives of aides and their supervisors on how technology interventions might contribute to moving aides towards a better future, we created a design provocation that centers aides' needs and suggests more equitable roles for them within the home care ecosystem. Findings from design sessions with 16 aides, nurses, and aide coordinators illuminate the ethical and pragmatic dilemmas inherent in this complex ecosystem, and show that designing technology for equity requires attention to structural problems in addition to workers' stated needs. We analyze our findings through the lens of social justice-oriented interaction design, and discuss how our work extends key strategies within this framework.

Be Water: Technologies in the Leaderless Anti-ELAB Movement in Hong Kong

We examine a leaderless social movement characterized by participants' autonomy and the absence of leaders and organizations. We conducted a participant observation study of the Anti-ELAB movement in Hong Kong. Focusing on the organization of a protest march, we collected thousands of lines of discourse in the LIHKG Forum and the Telegram instant messaging system. Our grounded theory analysis revealed hundreds of groups acting within a symbiotic network. Participants promoted an ethos of empowering individual participants and groups to act autonomously. At the same time, participants' extensive use of hyperlinks and polls orchestrated a coherent social movement. We discuss how this novel formation can mediate successful leaderless movements.

Adaptive Photographic Composition Guidance

Photographic composition is often taught as alignment with composition grids-most commonly, the rule of thirds. Professional photographers use more complex grids, like the harmonic armature, to achieve more diverse dynamic compositions. We are interested in understanding whether these complex grids are helpful to amateurs.

In a formative study, we found that overlaying the harmonic armature in the camera can help less experienced photographers discover and achieve different compositions, but it can also be overwhelming due to the large number of lines. Photographers actually use subsets of lines from the armature to explain different aspects of composition. However, this occurs mainly offline to analyze existing images. We propose bringing this mental model into the camera-by adaptively highlighting relevant lines to the current scene and point of view. We describe a saliency-based algorithm for selecting these lines and present an evaluation of the system that shows that photographers found the proposed adaptive armatures helpful for capturing more well-composed images.

Memory through Design: Supporting Cultural Identity for Immigrants through a Paper-Based Home Drafting Tool

Current research in HCI with immigrants predominantly focuses on their practical needs and little attention is given to their cultural identities. As such, we aim to understand how newcomers reflect their cultural values within domestic settings. We explore this by provoking memories immigrants associate with physical spaces inside their homes. Hence, we built "Our Home Sketcher": a paper-based home drafting tool that allows novice users to design their homes by sketching and implicitly expressing their space, light, and privacy preferences. The collected drawings are then fed into a computer algorithm that produces 3D models of the sketched houses. This process of design acts as an artifact-driven storytelling for heritage sharing and rapport building within migrant communities. We engage 13 Middle Eastern newcomers in Canada with the tool and use Halbwachs' [44] theory of collective memory to frame how home sketching provokes former experiences. Our findings show a strong longing for reclaiming the past, narrating space-related oral history, and designing beyond current limitations.

XRDirector: A Role-Based Collaborative Immersive Authoring System

Immersive authoring is an increasingly popular technique to design AR/VR scenes because design and testing can be done concurrently. Most existing systems, however, are single-user and limited to either AR or VR, thus constrained in the interaction techniques. We present XRDirector, a role-based collaborative immersive authoring system that enables designers to freely express interactions using AR and VR devices as puppets to manipulate virtual objects in 3D physical space. In XRDirector, we adapt roles known from filmmaking to structure the authoring process and help coordinate multiple designers in immersive authoring tasks. We study how novice AR/VR creators can take advantage of the roles and modes in XRDirector to prototype complex scenes with animated 3D characters, light effects, and camera movements, and also simulate interactive system behavior in a Wizard of Oz style. XRDirector's design was informed by case studies around complex 3D movie scenes and AR/VR games, as well as workshops with novice AR/VR creators. We show that XRDirector makes it easier and faster to create AR/VR scenes without the need for coding, characterize the issues in coordinating designers between AR and VR, and identify the strengths and weaknesses of each role and mode to mitigate the issues.

A Case for Humans-in-the-Loop: Decisions in the Presence of Erroneous Algorithmic Scores

The increased use of algorithmic predictions in sensitive domains has been accompanied by both enthusiasm and concern. To understand the opportunities and risks of these technologies, it is key to study how experts alter their decisions when using such tools. In this paper, we study the adoption of an algorithmic tool used to assist child maltreatment hotline screening decisions. We focus on the question: Are humans capable of identifying cases in which the machine is wrong, and of overriding those recommendations? We first show that humans do alter their behavior when the tool is deployed. Then, we show that humans are less likely to adhere to the machine's recommendation when the score displayed is an incorrect estimate of risk, even when overriding the recommendation requires supervisory approval. These results highlight the risks of full automation and the importance of designing decision pipelines that provide humans with autonomy.

Performance and Experience of Throwing in Virtual Reality

Throwing is a fundamental movement in many sports and games. Given this, accurate throwing in VR applications today is surprisingly difficult. In this paper we explore