CHI

Feedback is viewed as an essential element of ubiquitous computing systems in the HCI literature for helping people manage their privacy. However, the success of online social networks and existing commercial systems for mobile location sharing which do not incorporate feedback would seem to call the importance of feedback into question. We investigated this issue in the context of a mobile location sharing system. Specifically, we report on the findings of a field deployment of Locyoution, a mobile location sharing system. In our study, (n = 56), one group was given feedback in the form of a history of location requests, and a second group was given no feedback at all. Our major contribution has been to show that feedback is an important contributing factor towards improving user comfort levels and allaying privacy concerns. Participants' privacy concerns were reduced after using the mobile location sharing system. Additionally, our study suggests that peer opinion and technical savviness contribute most to whether or not participants thought they would continue to use a mobile location technology.

This paper presents a brief overview of findings collected from an ethnographic field study of young people and their use of mobile telephones. The findings indicate that mobile phones provide young people with a means of demonstrating their social networks. That is, through owning and using mobile phones, young people demonstrate their participation in social groupings and define the boundaries of their social networks. Using activity theory, the findings from this research have been interpreted to produce a number of preliminary design considerations. This work reflects the first of several stages aimed at investigating a systematic means of using rich and meaningful qualitative data for the purposes of design.

When looking out across the intellectual landscape of HCI, how do we make sense of it? More impor- tantly, how do we evaluate what constitutes legitimate investigation? As an interdisciplinary field, HCI faces challenges in incorporating sometimes conflicting intellectual approaches. While new approaches enrich our view of interaction, they can also lead to conflicting notions of methodology and validity, whose resolution remains murky without explicit discussion of their underlying epistemological commit- ments. Informal histories of HCI commonly identify two major intellectual waves that have formed the field: the first orienting from engineering and human factors with its focus on optimizing man-machine fit, and the second stemming from cognitive science, with an increased emphasis on theory and on what is happening not only in the computer but, simultaneously, in the human mind. HCI also draws on a wide variety of apparently disparate approaches, such as participatory design, si...

Media façades comprise a category of urban computing concerned with the integration of displays into the built environment, including buildings and street furniture. This paper identifies and discusses eight challenges faced when designing urban media façades. The challenges concern a broad range of issues: interfaces, physical integration, robustness, content, stakeholders, situation, social relations, and emerging use. The challenges reflect the fact that the urban setting as a domain for interaction design is characterized by a number of circumstances and sociocultural practices that differ from those of other domains. In order to exemplify the challenges and discuss how they may be addressed, we draw on our experiences from five experimental design cases, ranging from a 180 m 2 interactive building façade to displays integrated into bus shelters.

Medycyna Chińska należy do najstarszych w historii świata. Znajdujemy w nie, wiele wspaniałych wskazówek i analiz, niezwykle użyteczkol.tT d T J -F ; l0Z°flC2ne P°dsta^ -dycyn/chiński s ą komplementarne do medycyny zachodniej. Ta zaś, afirmując farmako* logiczne, chirurgiczne i "stechnicyzowane" leczenie, głównie objawów chorobowych bywa coraz częściej bezsilna, szczególnie w odniesieniu do tzw chorób cywilizacyjnych. Wydaje się oczywiste, że coraz bardziej potrzebujemy uzupełniania medycyny, bazujących głównie na objawach o wiedzę, która kładłaby nacisk na profilaktykę, wczesną diagnostykę; była bardziej ludzka i łatwiejsza w stosowaniu. Medycyna Chińska w pełni zaspokaja tę potrzebę i stąd też tak ogromne nią zainteresowanie.

We present data from detailed observation of 24 information workers that shows that they experience work fragmentation as common practice. We consider that work fragmentation has two components: length of time spent in an activity, and frequency of interruptions. We examined work fragmentation along three dimensions: effect of collocation, type of interruption, and resumption of work. We found work to be highly fragmented: people average little time in working spheres before switching and 57% of their working spheres are interrupted. Collocated people work longer before switching but have more interruptions. Most internal interruptions are due to personal work whereas most external interruptions are due to central work. Though most interrupted work is resumed on the same day, more than two intervening activities occur before it is. We discuss implications for technology design: how our results can be used to support people to maintain continuity within a larger framework of their working spheres.

This paper proposes a working definition of the term gamification as the use of game design elements in non-game contexts. This definition is related to similar concepts such as serious games, serious gaming, playful interaction, and game-based technologies.

Debugging is still among the most common and costly of programming activities. One reason is that current debugging tools do not directly support the inquisitive nature of the activity. Interrogative Debugging is a new debugging paradigm in which programmers can ask why did and even why didn't questions directly about their program's runtime failures. The Whyline is a prototype Interrogative Debugging interface for the Alice programming environment that visualizes answers in terms of runtime events directly relevant to a programmer's question. Comparisons of identical debugging scenarios from user tests with and without the Whyline showed that the Whyline reduced debugging time by nearly a factor of 8, and helped programmers complete 40% more tasks.

Although ethnography has become a common approach in HCI research and design, considerable confusion still attends both ethnographic practice and the criteria by which it should be evaluated in HCI. Often, ethnography is seen as an approach to field investigation that can generate requirements for systems development; by that token, the major evaluative criterion for an ethnographic study is the implications it can provide for design. Exploring the nature of ethnographic inquiry, this paper suggests that "implications for design" may not be the best metric for evaluation and may, indeed, fail to capture the value of ethnographic investigations.

Museums attract increasing numbers of online visitors along with their conventional physical visitors. This paper presents a study of a mixed reality system that allows web, virtual reality and physical visitors to share a museum visit together in real time. Our system allows visitors to share their location and orientation, communicate over a voice channel, and jointly navigate around a shared information space. Results from a study of 34 users of the system show that visiting with the system was highly interactive and retained many of the attractions of a traditional shared exhibition visit. Specifically, users could navigate together, collaborate around objects and discuss exhibits. These findings have implications for non-museum settings, in particular how location awareness is a powerful resource for collaboration, and how 'hybrid objects' can support collaboration at-a-distance.

Most current designs of information technology are based on the notion of supporting distinct tasks such as document production, email usage, and voice communication. In this paper we present empirical results that suggest that people organize their work in terms of much larger and thematically connected units of work. We present results of fieldwork observation of information workers in three different roles: analysts, software developers, and managers. We discovered that all of these types of workers experience a high level of discontinuity in the execution of their activities. People average about three minutes on a task and somewhat more than two minutes using any electronic tool or paper document before switching tasks. We introduce the concept of working spheres to explain the inherent way in which individuals conceptualize and organize their basic units of work. People worked in an average of ten different working spheres. Working spheres are also fragmented; people spend about 12 minutes in a working sphere before they switch to another. We argue that design of information technology needs to support people's continual switching between working spheres.

Ad-hoc virtual teams often lack tools to formalize leadership and structure collaboration, yet they are often successful. How does this happen? We argue that the emergence of leadership and the development of expertise occurs in the process of taking action and in direct response to a lack of structure. Using a twinned set of eight modality sliders, we examine the interactions of fourteen players in an alternate reality game. We find that players adopted military language and culture to structure and arrange their play. We determine that it is critical to account for the context of play across these modalities in order to design appropriately for effective in-game virtual organizing.

INTRODUCTION Musical performance with entirely new types of computer instruments is now commonplace, as a result of the availability of inexpensive computing hardware, of new sensors for measuring physical parameters such as force and position, and of new software for ...

We present a study that evaluates conventional Pan and Zoom Navigation and Rubber Sheet Navigation, a rectilinear Focus+Context technique. Each of the two navigation techniques was evaluated both with and without an overview. All interfaces guaranteed that regions of interest would remain visible, at least as a compressed landmark, independent of navigation actions. Interfaces implementing these techniques were used by 40 subjects to perform a task that involved navigating a large hierarchical tree dataset and making topological comparisons between nodes in the tree. Our results show that Pan and Zoom Navigation was significantly faster and required less mental effort than Rubber Sheet Navigation, independent of the presence or absence of an overview. Also, overviews did not appear to improve performance, but were still perceived as beneficial by users. We discuss the implications of our task and guaranteed visibility on the results and the limitations of our study, and we propose preliminary design guidelines and recommendations for future work.

Despite the abundance of research on social networking sites, relatively little research has studied those who choose not to use such sites. This paper presents results from a questionnaire of over 400 Internet users, focusing specifically on Facebook and those users who have left the service. Results show the lack of a clear, binary distinction between use and non-use, that various practices enable diverse ways and degrees of engagement with and disengagement from Facebook. Furthermore, qualitative analysis reveals numerous complex and interrelated motivations and justifications, both for leaving and for maintaining some type of connection. These motivations include: privacy, data misuse, productivity, banality, addiction, and external pressures. These results not only contribute to our understanding of online sociality by examining this under-explored area, but they also build on previous work to help advance how we conceptually account for the sociological processes of non-use.

According to usability experts, the top user issue for Web sites is difficult navigation. We have been developing automated usability tools for several years, and here we describe a prototype service called InfoScent™ Bloodhound Simulator, a pushbutton navigation analysis system, which automatically analyzes the information cues on a Web site to produce a usability report. We further build upon previous algorithms to create a method called Information Scent Absorption Rate, which measures the navigability of a site by computing the probability of users reaching the desired destinations on the site. Lastly, we present a user study involving 244 subjects over 1385 user sessions that shows how Bloodhound correlates with real users surfing for information on four Web sites. The hope is that, by using a simulation of user surfing behavior, we can reduce the need for human labor during usability testing, thus dramatically lowering testing costs, and ultimately improving user experience. The Bloodhound Project is unique in that we apply a concrete HCI theory directly to a real-world problem. The lack of empirically validated HCI theoretical models has plagued the development of our field, and this is a step toward that direction.

When on the move, cognitive resources are reserved partly for passively monitoring and reacting to contexts and events, and partly for actively constructing them. The Resource Competition Framework (RCF), building on the Multiple Resources Theory, explains how psychosocial tasks typical of mobile situations compete for cognitive resources and then suggests that this leads to the depletion of resources for task interaction and eventually results in the breakdown of fluent interaction. RCF predictions were tested in a semi-naturalistic field study measuring attention during the performance of assigned Web search tasks on mobile phone while moving through nine varied but typical urban situations. Notably, we discovered up to eight-fold differentials between micro-level measurements of attentional resource fragmentation, for example from spans of over 16 seconds in a laboratory condition dropping to bursts of just a few seconds in difficult mobile situations. By calibrating perceptual sampling, reducing resources from tasks of secondary importance, and resisting the impulse to switch tasks before finalization, participants compensated for the resource depletion. The findings are compared to previous studies in office contexts. The work is valuable in many areas of HCI dealing with mobility.

People often learn game-related information in video games by taking turns playing and watching each other play. This type of in-game learning involves both observation and imitation of actions. However, games are also made to be learnt individually during gameplay. Our study seeks to assess which is more effective for learning: just playing a game yourself or watching somebody play it first. We compare two gameplay situations: playing a digital game before watching a gameplay video and playing a digital game after watching a gameplay video. Using a between-participants design, to measure learning effectiveness we recorded Mu rhythms, which are indirectly linked to mirror neuron activation during imitation learning. We also analyze hemispheric frontal alpha asymmetry. Our results indicate that presentation order of the video game matters and players are more aroused when watching a gameplay video before playing.

The role of computers in the modern office has divided our activities between virtual interactions in the realm of the computer and physical interactions with real objects within the traditional office infrastructure. This paper extends previous work that has attempted to bridge this gap, to connect physical objects with virtual representations or computational functionality, via various types of tags. We discuss a variety of scenarios we have implemented using a novel combination of inexpensive, unobtrusive and easy to use RFID tags, tag readers, portable computers and wireless networking. This novel combination demonstrates the utility of invisibly, seamlessly and portably linking physical objects to networked electronic services and actions that are naturally associated with their form.

Systems able to find a song based on a sung, hummed, or whistled melody are called Query-By-Humming (QBH) systems. We propose an approach to improve search performance of a QBH system based on data collected from an online social music game, Karaoke Callout. Users of Karaoke Callout generate training data for the search engine, allowing both ongoing personalization of query processing as well as vetting of database keys. Personalization of search engine user models takes place through using sung examples generated in the course of play to optimize parameters of user models.

Background: Participation of protein polymorphism is often considered in the pathogenesis of various diseases. Aberrant protein glycosylation has been recognized to play major roles in human disorders, including neurodegenerative diseases. Objective: The aim of the study was to examine possible involvement of protein genetic variants and degree of glycosylation of some serum glycoproteins in the manifestation of neurodegenerative disorders in a Czech population sample. Methods: Apolipoprotein (Apo) E and three main serum markers of glycosylation defects (transferrin, Tf, alpha1-antitrypsin, aAT and ApoCIII) in patients with Alzheimer's dementia (AD), Parkinson's disease (PD) and vascular dementia (n = 62, 139 and 44, respectively) were analyzed by isoelectric focusing. Children with serious neurological symptoms (n = 55) and three age-matched control groups (n = 45, 45 and 42) were examined for comparison. Results: Of the supposedly pathognomonic protein variants Tf C2, aAT ZM and ApoE e4 only the latter was detected with higher frequency in AD patients; significant synergy of the C2/e4 allelic combination was not confirmed. The most prominent finding among PD adults was an increased appearance of Tf C2 allele and significant mean hypoglycosylation of ApoCIII, besides a C2/e4 positive correlation in PD seniors. Laboratory signs of Tf hypoglycosylation and a pattern of Tf/ApoCIII hyperglycosylation have been occasionally found.

Enabling users to identify trustworthy actors is a key design concern in online systems and expertise is a core dimension of trustworthiness. In this paper, we investigate (1) users' ability to identify expertise in advice and (2) effects of media bias in different representations. In a laboratory study, we presented 160 participants with two advisorsone represented by text-only; the other represented by one of four alternate formats: video, audio, avatar, or photo+text. Unknown to the participants, one was an expert (i.e. trained) and the other was a non-expert (i.e. untrained). We observed participants' advice seeking behavior under financial risk as an indicator of their trust in the advisor. For all rich media representations, participants were able to identify the expert, but we also found a tendency for seeking video and audio advice, irrespective of expertise. Avatar advice, in contrast, was rarely sought, but-like the other rich media representations-was seen as more enjoyable and friendly than text-only advice. In a future step we plan to analyze our data for effects on advice uptake.

Listening to music on personal, digital devices while mobile is an enjoyable, everyday activity. We explore a scheme for exploiting this practice to immerse listeners in navigation cues. Our prototype, Ontrack, continuously adapts audio, modifying the spatial balance and volume to lead listeners to their target destination. An initial lab-based evaluation has demonstrated the approach's efficacy: users were able to complete tasks within a reasonable time and their subjective feedback was positive. Encouraged by these findings, we are building a pocket-sized prototype for further testing.

We present data from detailed observation of 24 information workers that shows that they experience work fragmentation as common practice. We consider that work fragmentation has two components: length of time spent in an activity, and frequency of interruptions. We examined work fragmentation along three dimensions: effect of collocation, type of interruption, and resumption of work. We found work to be highly fragmented: people average little time in working spheres before switching and 57% of their working spheres are interrupted. Collocated people work longer before switching but have more interruptions. Most internal interruptions are due to personal work whereas most external interruptions are due to central work. Though most interrupted work is resumed on the same day, more than two intervening activities occur before it is. We discuss implications for technology design: how our results can be used to support people to maintain continuity within a larger framework of their working spheres.

Graphical authentication systems typically claim to be more usable than PIN or password-based systems, but these claims often follow limited, single-stage paradigm testing on a young, student population. We present a more demanding test paradigm in which multiple codes are learned and tested over a three-week period. We use this paradigm with two user populations, comparing the performance of younger and older adults. We first establish baseline performance in a study in which populations of younger and older adults learn PIN codes and we follow this with a second study in which younger and older adults use two face-based graphical authentication systems employing young faces vs. old faces as code components.

We present one possible design for a "wearable" computer-a computer that is worn. Our prototype permits text entry without the need of a table or other supporting surface. Typing can be performed while standing or even walking, Possible applications for this device are also discussed.

A major challenge that new college students face is the establishment of healthy habits that will affect their long-term health. Focusing on this difficult task is myPyramid: a dining hall service to support the development of healthy eating habits for busy and ...

This paper presents our work on the development of a multimodal auditory interface which permits blind users to work more easily and efficiently with GUI browsers. A macro-analysis phase, which can be either passive or active, informs on the global layout of HTML documents. A subsequent active micro-analysis phase allows to explore particular elements of the document. The interface is

Introduction Second Life is a user-driven online virtual world, originally conceived by Philip Rosedale, CEO of Linden Labs [7]. It is a “metaverse”, a term coined in Neal Stephenson's 1992 novel Snow Crash [10], in which people in real physical spaces create and maintain ...

In this paper we describe the development and use of a novel, practical approach to the design of a mobile multimedia terminal for a virtual community. The specific design goal was a dedicated mobile terminal concept for horse aficionados who belong to the virtual stables community. We had to use a creative approach since the design was for a device

This paper describes some of the consumer-driven usability research conducted by NCR Self Service Strategic Solutions in the development of an understanding of usability and user acceptance of leadingedge biometrics verification techniques. We discuss biometric techniques in general and focus upon the usability phases and issues, associated with iris verification technology at the Automated Teller Machine (ATM) user interface. The paper concludes with a review of some of the major research issues encountered, and an outline of future work in the area.

We present a new popup widget, called CoR2Ds (Context-Rooted Rotatable Draggables), designed for multi-user direct-touch tabletop environments. CoR2Ds are interactive callout popup objects that are visually connected (rooted) at the originating displayed object by a semi-transparent colored swath. CoR2Ds can be used to bring out meanus, display drilled-down or off-screen ancillary data such as metadata and attributes, as well as instantiate tools. CoR2Ds can be freely moved, rotated, and re-oriented on a tabletop display surface by fingers, hands, pointing devices (mice) or marking devices (such as a stylus or light pen). CoR2Ds address five issues for interaction techniques on interactive tabletop display surfaces: occlusion, reach, context on a cluttered display, readability, and concurrent/coordianted multi-user interaction. In this paper, we present the design, interaction and implementation of CoR2Ds. We also discuss a set of current usage scenarios.

We present data from detailed observation of 24 information workers that shows that they experience work fragmentation as common practice. We consider that work fragmentation has two components: length of time spent in an activity, and frequency of interruptions. We examined work fragmentation along three dimensions: effect of collocation, type of interruption, and resumption of work. We found work to be highly fragmented: people average little time in working spheres before switching and 57% of their working spheres are interrupted. Collocated people work longer before switching but have more interruptions. Most internal interruptions are due to personal work whereas most external interruptions are due to central work. Though most interrupted work is resumed on the same day, more than two intervening activities occur before it is. We discuss implications for technology design: how our results can be used to support people to maintain continuity within a larger framework of their working spheres.

Participatory Design is a common practice in HCI and user based evaluations are also highly recommended. This paper looks at the practice of carrying out design and evaluation sessions with school aged children by describing a general method for carrying out and arranging whole class activities that are school friendly and then by analyzing the academic value of these activities.

In this paper we argue that "persuasive technologies," developed to motivate behaviour change in users, have so far failed to exploit the established body of empirical research within behavioural science. We propose that persuasive technologies may benefit from both adapting to individual preferences, and a constructive use of aversive, in addition to appetitive, feedback. We detail an example application that demonstrates how this approach can be incorporated into an application designed to train users to adopt more environmentally friendly behaviours in their domestic kitchens.

Despite the abundance of research on social networking sites, relatively little research has studied those who choose not to use such sites. This paper presents results from a questionnaire of over 400 Internet users, focusing specifically on Facebook and those users who have left the service. Results show the lack of a clear, binary distinction between use and non-use, that various practices enable diverse ways and degrees of engagement with and disengagement from Facebook. Furthermore, qualitative analysis reveals numerous complex and interrelated motivations and justifications, both for leaving and for maintaining some type of connection. These motivations include: privacy, data misuse, productivity, banality, addiction, and external pressures. These results not only contribute to our understanding of online sociality by examining this under-explored area, but they also build on previous work to help advance how we conceptually account for the sociological processes of non-use.

We present data from detailed observation of 24 information workers that shows that they experience work fragmentation as common practice. We consider that work fragmentation has two components: length of time spent in an activity, and frequency of interruptions. We examined work fragmentation along three dimensions: effect of collocation, type of interruption, and resumption of work. We found work to be highly fragmented: people average little time in working spheres before switching and 57% of their working spheres are interrupted. Collocated people work longer before switching but have more interruptions. Most internal interruptions are due to personal work whereas most external interruptions are due to central work. Though most interrupted work is resumed on the same day, more than two intervening activities occur before it is. We discuss implications for technology design: how our results can be used to support people to maintain continuity within a larger framework of their working spheres.