Astral is a prototyping tool for authoring mobile and smart object interactive behaviours. It mirrors selected display contents of desktop applications onto mobile devices (smartphones and smartwatches), and streams/remaps mobile sensor data to desktop input events (mouse or keyboard) to manipulate selected desktop contents. This allows designers to use familiar desktop applications (e.g. PowerPoint, AfterEffects) to prototype rich interactive behaviours. Astral combines and integrates display mirroring, sensor streaming and input remapping, where designers can exploit familiar desktop applications to prototype, explore and fine-tune dynamic interactive behaviours. With Astral, designers can visually author rules to test real-time behaviours while interactions take place, as well as after the interaction has occurred. We demonstrate Astral's applicability, workflow and expressiveness within the interaction design process through both new examples and replication of prior approaches that illustrate how various familiar desktop applications are leveraged and repurposed.

Toolkit research plays an important role in the field of HCI, as it can heavily influence both the design and implementation of interactive systems. For publication, the HCI community typically expects toolkit research to include an evaluation component. The problem is that toolkit evaluation is challenging, as it is often unclear what 'evaluating' a toolkit means and what methods are appropriate. To address this problem, we analyzed 68 published toolkit papers. From our analysis, we provide an overview of, reflection on, and discussion of evaluation methods for toolkit contributions. We identify and discuss the value of four toolkit evaluation strategies, including the associated techniques that each employs. We offer a categorization of evaluation strategies for toolkit researchers, along with a discussion of the value, potential limitations, and trade-offs associated with each strategy.

Interactive, smart objects-customized to individuals and uses-are central to many movements, such as tangibles, the internet of things (IoT), and ubiquitous computing. Yet, rapid prototyping both the form and function of these custom objects can be problematic, particularly for those with limited electronics or programming experience. Designers often need to embed custom circuitry; program its workings; and create a form factor that not only reflects the desired user experience but can also house the required circuitry and electronics. To mitigate this, we created Pineal, a design tool that lets end-users: (1) modify 3D models to include a smart watch or phone as its heart; (2) specify high-level interactive behaviours through visual programming; and (3) have the phone or watch act out such behaviours as the objects' "smarts". Furthermore, a series of prototypes show how Pineal exploits mobile sensing and output, and automatically generates 3D printed form-factors for rich, interactive, objects.

Wall displays almost universally assume a mostly flat and static shape. We ask two questions: Would people choose a flat display for a given interaction scenario and, if not, what are the display shapes they actually prefer? We conducted a design study around these two questions. Our results show that participants designed different screen shapes that varied based upon peoples' distance from the display and the content shown. Shapes ranged primarily between flat, separated, concave, L-shape and convex displays. Based on our findings, we designed a dynamic display that changes to these and other configurations. Shape-shifting is controlled either by explicit interaction (where the display responds to hand gestures) or implicitly (where the display infers a shape based both on its content and the sensed positions of the people around it). Overall, we contribute: a study that motivates research on shape-shifting wall displays, and a shape-shifting display system that responds to explicit and implicit controls to match particular activities.

High-risk outdoor recreation allows its enthusiasts to reach unprecedented levels of adrenaline; it also contains risks and requires specific training (in part technological). In particular, its participants must be ready to react efficiently during an emergency or in response to an accident. Technological training grounds can simulate particular contexts and emergency situations as a place for recreationists to train and practice. In this paper, we use the practice of avalanche companion rescue as a case study to explore how technological training grounds support recreationist training. Our results offer insights into how avalanche beacon training parks support skill development and team coordination training. We also present strategies to orient the design of technological training grounds beyond avalanche companion rescue.

Stacked graphs are a visualization technique popular in casual scenarios for representing multiple time-series. Variations of stacked graphs have been focused on reducing the distortion of individual streams because foundational perceptual studies suggest that variably curved slopes may make it difficult to accurately read and compare values. We contribute to this discussion by formally comparing the relative readability of basic stacked area charts, ThemeRivers, streamgraphs and our own interactive technique for straightening baselines of individual streams in a ThemeRiver. We used both real-world and randomly generated datasets and covered tasks at the elementary, intermediate and overall information levels. Results indicate that the decreased distortion of the newer techniques does appear to improve their readability, with streamgraphs performing best for value comparison tasks. We also found that when a variety of tasks is expected to be performed, using the interactive version of the themeriver leads to more correctness at the cost of being slower for value comparison tasks.

Over a billion people use social networking sites like Facebook to maintain awareness of their friends. Facebook's News Feed is the primary mechanism by which people are shown updates about their friends' daily activities on the site in the form of an algorithmically curated list of stories. This paper examines how people browse the News Feed, their perceptions and satisfaction while using it, and the interactions they make with their personal social network. We conducted a qualitative study involving think-aloud semi-structured interviews as the participants casually browsed their own feeds. We observed a wide variation in the use of the News Feed ranging from careful consideration of social conventions, judgment of people, and annoyance and frustration towards certain friends. Our findings suggest that people do not deliberately curate their own News Feed either due to lack of awareness or perceived social repercussions.

Remote controls facilitate interactions at-a-distance with appliances. However, the complexity, diversity, and increasing number of digital appliances in ubiquitous computing ecologies make it increasingly difficult to: (1) discover which appliances are controllable; (2) select a particular appliance from the large number available; (3) view information about its status; and (4) control the appliance in a pertinent manner. To mitigate these problems we contribute proxemic-aware controls, which exploit the spatial relationships between a person's handheld device and all surrounding appliances to create a dynamic appliance control interface. Specifically, a person can discover and select an appliance by the way one orients a mobile device around the room, and then progressively view the appliance's status and control its features in increasing detail by simply moving towards it. We illustrate proxemic-aware controls of assorted appliances through various scenarios. We then provide a generalized conceptual framework that informs future designs of proxemic-aware controls.

Video chat systems such as Skype, Google+ Hangouts, and FaceTime have been widely adopted by family members and friends to connect with one another over distance. We have conducted a corpus of studies that explore how various demographics make use of such video chat systems in which this usage moves beyond the paradigm of conversational support to one in which aspects of everyday life are shared over long periods of time, sometimes in an almost passive manner. We describe and reflect on studies of long-distance couples, teenagers, and major life events, along with design research focused on new video communication systems—the Family Window, Family Portals, and Perch—that explicitly support “always-on video” for awareness and communication. Overall, our findings show that people highly value long-term video connections and have appropriated them in a number of different ways. Designers of future video communication systems need to consider: ways of supporting the sharing of everyday life rather than just conversation, providing different design solutions for different locations and situations, providing appropriate audio control and feedback, and supporting expressions of intimacy over distance.

Proxemics theory explains peoples' use of interpersonal distances to mediate their social interactions with others. Within Ubicomp, proxemic interaction researchers argue that people have a similar social understanding of their spatial relations with nearby digital devices, which can be exploited to better facilitate seamless and natural interactions. To do so, both people and devices are tracked to determine their spatial relationships. While interest in proxemic interactions has increased over the last few years, it also has a dark side: knowledge of proxemics may (and likely will) be easily exploited to the detriment of the user. In this paper, we offer a critical perspective on proxemic interactions in the form of dark patterns: ways proxemic interactions can be misused. We discuss a series of these patterns and describe how they apply to these types of interactions. In addition, we identify several root problems that underlie these patterns and discuss potential solutions that could lower their harmfulness.

We designed and operationalized a greetings model for human robot interaction as a state machine, derived from a subset of social behaviors as detailed by Kendon's observations of greetings and augmented by Hall's proxemics theory. Our premise is that designing robot greetings on the social science of human greetings will make the robot's greeting actions socially understandable. Specifically, we track the location and orientation of a Nao humanoid robot relative to a person, and programmed the robot via state transitions to engage in a distance salutation, approach, close salutation and transition as described by theory. Overall, our design appears effective in simulating social intelligence during greetings.

Transparent displays can serve as an important collaborative medium supporting face-to-face interactions over a shared visual work surface. Such displays enhance workspace awareness: when a person is working on one side of a transparent display, the person on the other side can see the other's body, hand gestures, gaze and what he or she is actually manipulating on the shared screen. Even so, we argue that designing such transparent displays must go beyond current offerings if it is to support collaboration. First, both sides of the display must accept interactive input, preferably by at least touch and / or pen, as that affords the ability for either person to directly interact with the workspace items. Second, and more controversially, both sides of the display must be able to present different content, albeit selectively. Third (and related to the second point), because screen contents and lighting can partially obscure what can be seen through the surface, the display should visually enhance the actions of the person on the other side to better support workspace awareness. We describe our prototype FACINGBOARD-2 system, where we concentrate on how its design supports these three collaborative requirements.

Digital games are increasingly profiting from sensing technologies. However, their focus is mostly on sensing limb movements. We propose that sensing capabilities could also be used to engage players with proxemics: the interpersonal distance between players. We further add that wireless networks offer complementary distance zones for designers, offering novel design resources for digital play. We use our own as well as other games to articulate a set of strategies on how designers can utilize both proxemics and the new wireless proxemics to facilitate novel play experiences. Ultimately, with our work, we aim to expand the range of digital play.

When facing an avalanche, backcountry skiers need to work effectively both individually and as a group to rescue buried victims. If they don't, death is likely. One of the tools used by each person is a digital beacon that transmits an electromagnetic signal. If buried, others use their beacons to locate victims by searching for their signals, and then dig them out. This study focuses on the collaborative practices of avalanche rescue and the interactions with beacons while backcountry skiing. We conducted interviews with backcountry recreationists and experts, and we observed avalanche rescue practice scenarios. Our results highlight aspects and challenges of mental representation, trust, distributed cognition, and practice. Implications include three considerations for the redesign of beacons: simplicity, visibility and practice.

There is a well-established culture of early prototyping when designing digital interactive systems, such as paper prototyping and wireframe methods. The culture of designing physical objects is somewhat different: early explorations of form is still prototyped via 2D sketches or renderings, but - mostly because of the construction effort involved - prototyping of actual physical objects is deferred to later stages. A problem occurs when designing mixed physical-digital systems, such as tangible user interfaces (TUIs) on interactive surfaces: the high degree of interactivity means that early prototyping is vital, yet there is no viable process for prototyping both the physical and digital aspects simultaneously on a low-fidelity (low-fi) level. Our solution is Paperbox, a toolkit for exploring design ideas for tangible interaction on interactive surfaces. It supports the early exploration of different form factors and immediately provides digital interactivity for the low-fidelity TUI prototypes built with it. We observed our toolkit in use in various settings: as a brainstorming tool by junior designers; in the development of a consumer electronics product in a large industrial company by senior designers; and in a usability study comparing the effect of different levels of fidelity on the outcome. The lessons learnt will enable others to replicate and extend our approach.

Researchers have developed interaction concepts based on mobile projectors. Yet pursuing work in this area - particularly in building projector-based interactions techniques within an application - is cumbersome and time-consuming. To mitigate this problem, we contribute ProjectorKit, a flexible open-source toolkit that eases rapid prototyping mobile projector interaction techniques.

This paper addresses the need of interpersonal privacy coordination mechanisms in the context of mediated communication, emphasizing the dialectic and dynamic nature of privacy. We contribute the Privacy Grounding Model—built upon the Common Ground theory—that describes how connected individuals create and adapt privacy borders dynamically and in a collaborative process. We present the theoretical foundations of the model. We also show the applicability of the model, where we give evidence from a field study that illustrates how it can describe privacy coordination mechanisms amongst users of an instant messaging application and a desktop awareness system. The model describes efficient and effective factors that communicators consider in their decisions to use mechanisms for coordination. The Privacy Grounding Model aims to help designers reflect on how their system supports, or fails to support, people’s need for lightweight and distinctive privacy coordination mechanisms, and in particular how communicators within the system create and use privacy border representations for grounding their needs to interact with each other.

Portable paper calendars (i. e., day planners and organizers) have greatly influenced the design of group electronic calendars. Both use time units (hours/days/weeks/etc.) to organize visuals, with useful information (e.g., event types, locations, attendees) usually presented as - perhaps abbreviated or even hidden - text fields within those time units. The problem is that, for a group, this visual sorting of individual events into time buckets conveys only limited information about the social network of people. For example, people's whereabouts cannot be read 'at a glance' but require examining the text. Our goal is to explore an alternate visualization that can reflect and illustrate group members' calendar events. Our main idea is to display the group's calendar events as spatiotemporal activities occurring over a geographic space animated over time, all presented on a highly interactive public display. In particular, our Spalendar (Spatial Calendar) design animates people's past, present and forthcoming movements between event locations as well as their static locations. Detail of people's events, their movements and their locations is progressively revealed and controlled by the viewer's proximity to the display, their identity, and their gestural interactions with it, all of which are tracked by the public display.

Many couples live a portion of their lives in a long-distance relationship (LDR). This includes a large number of dating college students as well as couples who are geographically-separated because of situational demands such as work. We conducted interviews with individuals in LDRs to understand how they make use of video chat systems to maintain their relationships. In particular, we have investigated how couples use video to "hang out" together and engage in activities over extended periods of time. Our results show that regardless of the relationship situation, video chat affords a unique opportunity for couples to share presence over distance, which in turn provides intimacy. While beneficial, couples still face challenges in using video chat, including contextual (e.g., location of partners, time zones), technical (e.g., mobility, audio/video quality, networking), and personal (e.g., a lack of physicality needed by most for intimate sexual acts) challenges.

Modern mobile devices allow a rich set of multi-finger interactions that combine modes into a single fluid act, for example, one finger for panning blending into a two-finger pinch gesture for zooming. Such gestures require the use of both hands: one holding the device while the other is interacting. While on the go, however, only one hand may be available to both hold the device and interact with it. This mostly limits interaction to a single-touch (i.e., the thumb), forcing users to switch between input modes explicitly. In this paper, we contribute the Fat Thumb interaction technique, which uses the thumb's contact size as a form of simulated pressure. This adds a degree of freedom, which can be used, for example, to integrate panning and zooming into a single interaction. Contact size determines the mode (i.e., panning with a small size, zooming with a large one), while thumb movement performs the selected mode. We discuss nuances of the Fat Thumb based on the thumb's limited operational range and motor skills when that hand holds the device. We compared Fat Thumb to three alternative techniques, where people had to precisely pan and zoom to a predefined region on a map and found that the Fat Thumb technique compared well to existing techniques.

Modern mobile devices rely on the screen as a primary input modality. Yet the small screen real-estate limits interaction possibilities, motivating researchers to explore alternate input techniques. Within this arena, our goal is to develop Body-Centric Interaction with Mobile Devices: a class of input techniques that allow a person to position and orient her mobile device to navigate and manipulate digital content anchored in the space on and around the body. To achieve this goal, we explore such interaction in a bottom-up path of prototypes and implementations. From our experiences, as well as by examining related work, we discuss and present three recurring themes that characterize how these interactions can be realized. We illustrate how these themes can inform the design of Body-Centric Interactions by applying them to the design of a novel mobile browser application. Overall, we contribute a class of mobile input techniques where interactions are extended beyond the small screen, and are instead driven by a person's movement of the device on and around the body.

In the real world, touch based interaction relies on haptic feedback (e.g., grasping objects, feeling textures). Unfortunately, such feedback is absent in current tabletop systems. The previously developed Haptic Tabletop Puck (HTP) aims at supporting experimentation with and development of inexpensive tabletop haptic interfaces in a do-it-yourself fashion. The problem is that programming the HTP (and haptics in general) is difficult. To address this problem, we contribute the Haptictouch toolkit, which enables developers to rapidly prototype haptic tabletop applications. Our toolkit is structured in three layers that enable programmers to: (1) directly control the device, (2) create customized combinable haptic behaviors (e.g., softness, oscillation), and (3) use visuals (e.g., shapes, images, buttons) to quickly make use of these behaviors. In our preliminary exploration we found that programmers could use our toolkit to create haptic tabletop applications in a short amount of time.

Graspable tangibles are now being explored on the current generation of capacitive touch surfaces, such as the iPad and the Android tablet. Because the size and form factor is relatively new, early and low fidelity prototyping of these TUIs is crucial in getting the right design. The problem is that it is difficult for the average interaction designer to develop such physical prototypes. They require a substantial amount time and effort to physically model the tangibles, and expertise in electronics to instrument them. Thus prototyping is sometimes handed off to specialists, or is limited to only a few design iterations and alternative designs. Our solution contributes a low fidelity prototyping approach that is time and cost effective, and that requires no electronics knowledge. First, we supply non-specialists with cardboard forms to create tangibles. Second, we have them draw lines on it via conductive ink, which makes their objects recognizable by the capacitive touch screen. They can then apply routine programming to recognize these tangibles and thus iterate over various designs.

GroupTogether is a system that explores cross-device interaction using two sociological constructs. First, F-formations concern the distance and relative body orientation among multiple users, which indicate when and how people position themselves as a group. Second, micro-mobility describes how people orient and tilt devices towards one another to promote fine-grained sharing during co-present collaboration. We sense these constructs using: (a) a pair of overhead Kinect depth cameras to sense small groups of people, (b) low-power 8GHz band radio modules to establish the identity, presence, and coarse-grained relative locations of devices, and (c) accelerometers to detect tilting of slate devices. The resulting system supports fluid, minimally disruptive techniques for co-located collaboration by leveraging the proxemics of people as well as the proxemics of devices.

Phishers are fraudsters that mimic legitimate websites to steal user's credenfitial information and exploit that information for identity theft and other criminal activities. Various anti-phishing techniques attempt to mitigate such attacks. Domain highlighting is one such approach recently incorporated by several popular web browsers. The idea is simple: the domain name of an address is highlighted in the address bar, so that users can inspect it to determine a web site's legitimacy. Our research asks a basic question: how well does domain highlighting work? To answer this, we showed 22 participants 16 web pages typical of those targeted for phishing attacks, where participants had to determine the page's legitimacy. In the first round, they judged the page's legitimacy by whatever means they chose. In the second round, they were directed specifically to look at the address bar. We found that participants fell into 3 types in terms of how they determined the legitimacy of a web page; while domain highlighting was somewhat effective for one user type, it was much less effective for others. We conclude that domain highlighting, while providing some benefit, cannot be relied upon as the sole method to prevent phishing attacks.

The rising popularity of digital table surfaces has spawned considerable interest in new interaction techniques. Most interactions fall into one of two modalities: 1) direct touch and multi-touch (by hand and by tangibles) directly on the surface, and 2) hand gestures above the surface. The limitation is that these two modalities ignore the rich interaction space between them. To move beyond this limitation, we first contribute a unification of these discrete interaction modalities called the continuous interaction space . The idea is that many interaction techniques can be developed that go beyond these two modalities, where they can leverage the space between them. That is, we believe that the underlying system should treat the space on and above the surface as a continuum , where a person can use touch, gestures, and tangibles anywhere in the space and naturally move between them. Our second contribution illustrates this, where we introduce a variety of interaction categories that exploit the space between these modalities. For example, with our Extended Continuous Gestures category, a person can start an interaction with a direct touch and drag, then naturally lift off the surface and continue their drag with a hand gesture over the surface. For each interaction category, we implement an example (or use prior work) that illustrates how that technique can be applied. In summary, our primary contribution is to broaden the design space of interaction techniques for digital surfaces, where we populate the continuous interaction space both with concepts and examples that emerge from considering this space as a continuum.

Designing robotic behaviours capable of initiating an interruption will be extremely important as robots increasingly interact with people. Consequently, we explore the social impact of a minimal set of physical nonverbal cues that can be exhibited by a robot to initiate robot-human interruption: (a) speed of motion, (b) gaze, (c) head movement, d) rotation and (e) proximity to the person. We present two related studies evaluating this set. First, for requirements gathering, we observed the behaviour of interruption between humans, with a human actor attempting to interrupt other humans while being constrained to use only a set of behavioural cues that could be mimicked by a simple nonverbal robot. Next, we programmed a robot to exhibit similar social physical nonverbal cues, and tested their feasibility in a user study of robotic nonverbal interruption across interruption scenarios. Our results show that people were able to interpret interruption urgency from robot behaviour using only minimal nonverbal behavioural cues. These findings contribute to informing future designs of social human-robot interfaces.

People naturally understand and use proxemic relationships (e.g., their distance and orientation towards others) in everyday situations. However, only few ubiquitous computing (ubicomp) systems interpret such proxemic relationships to mediate interaction (proxemic interaction). A technical problem is that developers find it challenging and tedious to access proxemic information from sensors. Our Proximity Toolkit solves this problem. It simplifies the exploration of interaction techniques by supplying fine-grained proxemic information between people, portable devices, large interactive surfaces, and other non-digital objects in a room-sized environment. The toolkit offers three key features. 1) It facilitates rapid prototyping of proxemic-aware systems by supplying developers with the orientation, distance, motion, identity, and location information between entities. 2) It includes various tools, such as a visual monitoring tool, that allows developers to visually observe, record and explore proxemic relationships in 3D space. (3) Its flexible architecture separates sensing hardware from the proxemic data model derived from these sensors, which means that a variety of sensing technologies can be substituted or combined to derive proxemic information. We illustrate the versatility of the toolkit with proxemic-aware systems built by students.

Global warming, and the climate change it induces, is an urgent global issue. One remedy to this problem, and the focus of this paper, is to motivate sustainable energy usage behaviors by people. One approach is the development of technologies that provide real-time, continuous feedback of energy usage. However, there is one problem - most tech-nologies use a one-size-fits-all solution, providing the same feedback to differently motivated individuals at different stages of readiness, willingness and ableness to change. In this paper, we synthesize a wide range of motivational psychology literature to develop a motivational framework based on the Transtheoretical (aka Stages of Behavior Change) Model. For each stage, we state the mo-tivational goal(s), and recommendation(s) for how technol-ogies can reach these goals. Each goal and recommendation is supported by a rationale based on motivational literature. Each recommendation is supported by a simple textual example illustrating one way to apply the recommendation.

People now routinely carry radio frequency identification (RFID) tags - in passports, driver's licenses, credit cards, and other identifying cards - from which nearby RFID readers can access privacy-sensitive information. The problem is that people are often unaware of security and privacy risks associated with RFID, likely because the technology remains largely invisible and uncontrollable for the individual. To mitigate this problem, we introduce a collection of novel yet simple and inexpensive tag designs. Our tags provide reader awareness, where people get visual, audible, or tactile feedback as tags come into the range of RFID readers. Our tags also provide information control, where people can allow or disallow access to the information stored on the tag by how they touch, orient, move, press or illuminate the tag.

Issue tracking systems help organizations manage issue reporting, assignment, tracking, resolution, and archiving. Traditionally, it is the Software Engineering community that researches issue tracking systems, where software defects are reported and tracked as 'bug reports' within an archival database. Yet, as issue tracking is fundamentally a social process, it is important to understand the design and use of issue tracking systems from that perspective. Consequently, we conducted a qualitative study of issue tracking systems as used by small, collocated software development teams. We found that an issue tracker is not just a database for tracking bugs, features, and inquiries, but also a focal point for communication and coordination for many stakeholders within and beyond the software team. Customers, project managers, quality assurance personnel, and programmers all contribute to the shared knowledge and persistent communication that exists within the issue tracking system. These results were all the more striking because in spite of teams being collocated--which afforded frequent, face-to-face communication--the issue tracker was still used as a fundamental communication channel. We articulate various real-world practices surrounding issue trackers and offer design considerations for future systems.

In this paper, we present results from a study of collocated group console gaming. We focus, in particular, on observed gaming practices that emphasized the individual gamer within a gaming group as well as practices that emphasized the gaming group as a whole. We relate each of these practices, where possible, to specific elements of the game design including game mechanics, interaction design, and special effects design. We argue that the classic distinction between competitive and cooperative modes of gameplay does not fully transfer to account for the interpersonal dynamics within collocated gaming groups.

Lightweight group meetings are opportunistic, ad-hoc, or lightly planned gatherings characterized by the informal nature of their members and their tasks. Critically, they must be very easy to set up and maintain over time. We contribute the design of Come Together, a system that supports lightweight, persistent meetings between distance-separated people. Its design is theoretically motivated by the Locales Framework, with features derived from the best of Instant Messengers and the Community Bar. Its main motivation is that any action must be simple and fast to do if it is to support lightweight group meetings. In particular, Come Together represents both people and their things as media items, which - unlike prior systems - can be quickly brought together to form an ad hoc place. Places, which are persistent, can be presented in a variety of forms (e.g., as a stand-alone window, or as an element in a sidebar), with interaction mechanisms that let a person quickly adjust the degree of awareness he or she wishes to maintain of the place and its contents. Somewhat akin to buddy lists, a console collects all people, artifacts, and places, where users can select them to rapidly compose meeting places.

We are interested in exploring how robots controlled using Wizard of Oz (WoO) should interrupt humans in various social settings. While there is considerable work on interruption and interruptibility in HCI, little has been done to explore how these concepts will map robotic interaction. As part of our efforts to investigate interruption and interruptibility in HRI we used WoO-based methodology to investigate robot behaviours in a simple interruption scenario. In this report we contribute a design critique that discusses this methodology, and common concerns that could be generalized to other social HRI experiments as well as reflections on our future interruption HRI research.

Distributed physical user interfaces comprise networked sensors, actuators and other devices attached to a variety of computers in different locations. Developing such systems is no easy task. It is hard to track the location and status of component devices, even harder to understand, validate, test and debug how events are transmitted between devices, and hardest yet to see if the overall system behaves correctly. Our Visual Environment Explorer supports developers of these systems by visualizing the location and status of individual and/or aggregate devices. It visualizes the current event flow between devices as they are received and transmitted, as well as the event history. Events are displayable at various levels of detail. The visualization also shows the activity of applications that use these physical devices. The tool is highly interactive: developers can explore system behavior through spatial navigation, zooming, multiple simultaneous views, event filtering, details-on-demand, and time-dependent semantic zooming.

In this paper, we show that people frequently return to previously-visited regions within their documents, and that scrollbars can be enhanced to ease this task. We analysed 120 days of activity logs from Microsoft Word and Adobe Reader. Our analysis shows that region revisitation is a common activity that can be supported with relatively short recency lists. This establishes an empirical foundation for the design of an enhanced scrollbar containing scrollbar marks that helps people return to previously visited document regions. Two controlled experiments show that scrollbar marks decrease revisitation time, and that a large number of marks can be used effectively. We then design an enhanced Footprints scrollbar that supports revisitation with several features, including scrollbar marks and mark thumbnails. Two further experiments show that the Footprints scrollbar was frequently used and strongly preferred over traditional scrollbars.

In this paper, we present results from a qualitative study of collocated group console gaming. We focus on motivations for, perceptions of, and practices surrounding the shared use of console games by a variety of established groups of gamers. These groups include both intragenerational groups of youth, adults, and elders as well as intergenerational families. Our analysis highlights the numerous ways that console games serve as a computational meeting place for a diverse population of gamers.

Hierarchical file systems and file browsers offer powerful capabilities for managing and organizing folders and files. Yet they lack robust tools for annotating and documenting these files-individually or collectively-with descriptive text. In contrast, Web pages and wikis make it easy to create rich and meaningful narratives around digital artifacts, allowing files to be embedded within explanatory text and images. Unfortunately, considerable effort is required to manage files stored on Web servers and to ensure that the published content remains up-to-date. In this note, we describe WikiFolders, a hybrid system for annotating file folders that draws upon the strengths of both the hierarchical file system and wikis.

In this paper, we explore the practice of using a whiteboard for multiple tasks, and specifically how users employ whiteboards to smoothly transition between related sets of tasks. Our study underscores several basic, but important affordances of whiteboards that support this practice, including visual persistence, flexibility of interaction primitives, and their situated physicality. We discuss the implications of these findings for the design of large display applications.

Computation is increasingly prevalent in the home: it serves as a way to control the home itself, or it is part of the many digital appliances within it. The question is: how can home inhabitants effectively understand and control the digital home? Our solution lets a person examine and control their home surroundings through a mobile display that serves as a 'magic lens', where the detail shown varies with proximity. In particular, HomeWindow is an augmented reality system that superimposes an interactive graphical interface atop of physical but digital artifacts in the home. One can get an overview of a room's computational state by looking through the display: the basic state of all digital hot spots are shown atop their physical counterparts. As one approaches a particular digital spot, more detailed information as well as a control interface is shown using a semantic zoom. Our current implementation works with two home devices. First, people can examine and remotely control the status of mobile domestic robots. Second, people can discover the power consumption of household appliances, where appliances are surrounded by a colorful aura that reflects its current and historical energy use.

An ongoing issue in human robot interaction (HRI) is how people and robots communicate with one another. While there is considerable work in real-time human-robot communication, fairly little has been done in asynchronous realm. Our approach, which we call situated messages, lets humans and robots asynchronously exchange information by placing physical tokens - each representing a simple message - in meaningful physical locations of their shared environment. Using knowledge of the robot's routines, a person can place a message token at a location, where the location is typically relevant to redirecting the robot's behavior at that location. When the robot passes nearby that location, it detects the message and reacts accordingly. Similarly, robots can themselves place tokens at specific locations for people to read. Thus situated messages leverages embodied interaction, where token placement exploits the everyday practices and routines of both people and robots. We describe our working prototype, introduce application scenarios, explore message categories and usage patterns, and suggest future directions.

Several emerging computer devices read bio-electrical signals (e.g., electro-corticographic signals, skin biopotential or facial muscle tension) and translate them into computer- understandable input. We investigated how one low-cost commercially-available device could be used to control a domestic robot. First, we used the device to issue direct motion commands; while we could control the device somewhat, it proved difficult to do reliably. Second, we interpreted one class of signals as suggestive of emotional stress, and used that as an emotional parameter to influence (but not directly control) robot behaviour. In this case, the robot would react to human stress by staying out of the person's way. Our work suggests that affecting behaviour may be a reasonable way to leverage such devices.

The uptake of digital photos vs. print photos has altered the practice of photo-sharing. Print photos are easy to share within the home, but much harder to share outside of it. The opposite is true of digital photos. People easily share digital photos outside the home, e.g., to family and friends by e-mail gift-giving, and to social networks and the broader public by web publishing. Yet within the home, collocated digital photo-sharing is harder, primarily because digital photos are typically stored on personal accounts in desktop computers located in home offices. This leads to several consequences. (1) The invisibility of digital photos implies few opportunities for serendipitous photo-sharing. (2) Access control and navigation issues inhibit family members from retrieving photo collections. (3) Photo viewing is compromised as digital photos are displayed on small screens in an uncomfortable viewing setting. To mitigate some of these difficulties, we explore how physical memorabilia collected by family members can create opportunities that encourage social and collocated digital photo-sharing. First, we studied (via contextual interviews with 20 households) how families currently practice photo-sharing and how they keep memorabilia. We identified classes of memorabilia that can serve as memory triggers to family events, trips, and times when people took photos. Second, we designed Souvenirs, a photo-viewing system that exploits memorabilia as a social instrument. Using Souvenirs, a family member can meaningfully associate physical memorabilia with particular photo-sets. Later, any family member can begin their story-telling with others through the physical memento, and then enrich the story by displaying its associated photos simply by moving the memento close to the home's large-format television screen. Third, we re-examined our design premises by evoking household reactions to an early version of Souvenirs. Based on these interviews, we redesigned Souvenirs to better reflect the preferences and real practices of photo and memorabilia use in the home.

Everyday family life involves a myriad of mundane activities that need to be planned and coordinated. We describe findings from studies of 44 different families' calendaring routines to understand how to best design technology to support them. We outline how a typology of calendars containing family activities is used by three different types of families— monocentric , pericentric , and polycentric —which vary in the level of family involvement in the calendaring process. We describe these family types, the content of family calendars, the ways in which they are extended through annotations and augmentations, and the implications from these findings for design.

People now easily share digital photos outside the home via web publishing and gift-giving. Yet within the home, digital photos are hard to access and lack the physical affordances that make sharing easy and opportunistic. To promote in-home photo sharing, we designed Souvenirs, a system that lets people link digital photo sets to physical memorabilia. These mementos trigger memories and serve as social instruments; a person can enrich their story-telling by moving the physical memento close to their large-format television screen, and the associated photos are immediately displayed. We implemented Souvenirs, and then re-examined our design premises through contextual interviews with 20 households. Families described their current practices of photo sharing and memento use, and also reacted to the Souvenirs design. Based on these interviews, we redesigned Souvenirs to better fit the real practices of photo and memento use in the home.

True multi-user, multimodal interaction over a digital table lets co-located people simultaneously gesture and speak commands to control an application. We explore this design space through a case study, where we implemented an application that supports the KJ creativity method as used by industrial designers. Four key design issues emerged that have a significant impact on how people would use such a multi-user multimodal system. First, parallel work is affected by the design of multimodal commands. Second, individual mode switches can be confusing to collaborators, especially if speech commands are used. Third, establishing personal and group territories can hinder particular tasks that require artefact neutrality. Finally, timing needs to be considered when designing joint multimodal commands. We also describe our model view controller architecture for true multi-user multimodal interaction.

Video slicing---a variant of slit scanning in photography---extracts a scan line from a video frame and successively adds that line to a composite image over time. The composite image becomes a time line, where its visual patterns reflect changes in a particular area of the video stream. We extend this idea of video slicing by allowing users to draw marks anywhere on the source video to capture areas of interest. These marks, which we call slit-tears, are used in place of a scan line, and the resulting composite timeline image provides a much richer visualization of the video data. Depending on how tears are placed, they can accentuate motion, small changes, directional movement, and relational patterns.

Instructor/student interaction in e-learning environments can positively impact both student learning and instructor satisfaction. In online webcast lectures, however, interaction can be difficult because instructors lack basic awareness information about their remote students. Our goal is to better understand the kinds of awareness information that instructors should have if they are to interact frequently and effectively with their students in e-learning environments. We conducted an exploratory study -- via interviews and observations -- of instructor attention in face-to-face classrooms at a large university. Our results imply that a webcast system should provide instructors with overview and detailed data about their students, but that this detailed information should not be displayed publicly.

Current practice in Human Computer Interaction as encouraged by educational institutes, academic review processes, and institutions with usability groups advocate usability evaluation as a critical part of every design process. This is for good reason: usability evaluation has a significant role to play when conditions warrant it. Yet evaluation can be ineffective and even harmful if naively done ‘by rule ’ rather than ‘by thought’. If done during design brainstorming, it can kill creative ideas that do not conform to current interface norms. If done prematurely during early system design, the many interface issues seen can kill what would could have been an inspired vision. If done to verify an academic prototype, it may incorrectly suggest a design’s worthiness rather than offer a meaningful critique of how it would be adopted and used in everyday practice. If done without regard to how cultures adopt technology over time, then today's reluctant reactions by users will forestall tomorrow's eager acceptance. Traditional usability evaluation should not be used to validate very early design stages or culturally-sensitive systems. Other reflective and critical methods should be considered in their stead. Author Keywords Usability testing, interface critiques, sketching, cultural

In any collaborative system, there are both symmetries and asymmetries present in the design of the technology and in the ways that technology is appropriated. Yet media space research tends to focus more on supporting and fostering the symmetries than the asymmetries. Throughout more than 20 years of media space research, the pursuit of increased symmetry, whether achieved through technical or social means, has been a recurrent theme. The research literature on the use of contemporary awareness systems, in contrast, displays little if any of this emphasis on symmetrical use; indeed, this body of research occasionally highlights the perceived value of asymmetry. In this paper, we unpack the different forms of asymmetry present in both media spaces and contemporary awareness systems. We argue that just as asymmetry has been demonstrated to have value in contemporary awareness systems, so might asymmetry have value in media spaces and in other CSCW systems, more generally. To illustrate, we present a media space that emphasizes and embodies multiple forms of asymmetry and does so in response to the needs of a particular work context.

Menus are a primary control in current interfaces, but there has been relatively little theoretical work to model their performance. We propose a model of menu performance that goes beyond previous work by incorporating components for Fitts' Law pointing time, visual search time when novice, Hick-Hyman Law decision time when expert, and for the transition from novice to expert behaviour. The model is able to predict performance for many different menu designs, including adaptive split menus, items with different frequencies and sizes, and multi-level menus. We tested the model by comparing predictions for four menu designs (traditional menus, recency and frequency based split menus, and an adaptive 'morphing' design) with empirical measures. The empirical data matched the predictions extremely well, suggesting that the model can be used to explore a wide range of menu possibilities before implementation.

Co-located collaborators often work over physical tabletops using combinations of expressive hand gestures and verbal utterances. This paper provides the first observations of how pairs of people communicated and interacted in a multimodal digital table environment built atop existing single user applications. We contribute to the understanding of these environments in two ways. First, we saw that speech and gesture commands served double duty as both commands to the computer, and as implicit communication to others. Second, in spite of limitations imposed by the underlying single-user application, people were able to work together simultaneously, and they performed interleaving acts: the graceful mixing of inter-person speech and gesture actions as commands to the system. This work contributes to the intricate understanding of multi-user multimodal digital table interaction.

Ethnographic studies of the home revealed the fundamental roles that physical locations and context play in how household members understand and manage conventional information. Yet we also know that digital information is becoming increasingly important to households. The problem is that this digital information is almost always tied to traditional computer displays, which inhibits its incorporation into household routines. Our solution, location-dependent information appliances, exploit both home location and context (as articulated in ethnographic studies) to enhance the role of ambient displays in the home setting; these displays provide home occupants with both background awareness of an information source and foreground methods to gain further details if desired. The novel aspect is that home occupants assign particular information to locations within a home in a way that makes sense to them. As a device is moved to a particular home location, information is automatically mapped to that device along with hints on how it should be displayed.

Digital family calendars have the potential to help families coordinate, yet they must be designed to easily fit within existing routines or they will simply not be used. To understand the critical factors affecting digital family calendar design, we extended LINC, an inkable family calendar to include ubiquitous access, and then conducted a month-long field study with four families. Adoption and use of LINC during the study demonstrated that LINC successfully supported the families' existing calendaring routines without disrupting existing successful social practices. Families also valued the additional features enabled by LINC. For example, several primary schedulers felt that ubiquitous access positively increased involvement by additional family members in the calendaring routine. The field trials also revealed some unexpected findings, including the importance of mobility---both within and outside the home---for the Tablet PC running LINC.

Community Bar (CB) is groupware supporting informal awareness and casual interaction. CB's design was derived from three sources: prior empirical research findings concerning informal awareness and casual interaction, a comprehensive sociological theory called the Locales Framework, and the Focus/Nimbus model of awareness. We conducted a field study of a group's on-going CB use. We use its results to reflect upon the matches and mis-matches that occurred between the theoretical and actual usage behaviors anticipated by our design principles vs. those observed in our deployment. As a critique, this reflectionis an important iterative step in recognizing flaws not just as usability problems, but as an incorrect translation of theory into design that can be re-analyzed from a theoretical perspective.

The rapid development of large interactive wall displays has been accompanied by research on methods that allow people to interact with the display at a distance. The basic method for target acquisition is by ray casting a cursor from one's pointing finger or hand position; the problem is that selection is slow and error-prone with small targets. A better method is the bubble cursor that resizes the cursor's activation area to effectively enlarge the target size. The catch is that this technique's effectiveness depends on the proximity of surrounding targets: while beneficial in sparse spaces, it is less so when targets are densely packed together. Our method is the speech-filtered bubble ray that uses speech to transform a dense target space into a sparse one. Our strategy builds on what people already do: people pointing to distant objects in a physical workspace typically disambiguate their choice through speech. For example, a person could point to a stack of books and say "the green one". Gesture indicates the approximate location for the search, and speech 'filters' unrelated books from the search. Our technique works the same way; a person specifies a property of the desired object, and only the location of objects matching that property trigger the bubble size. In a controlled evaluation, people were faster and preferred using the speech-filtered bubble ray over the standard bubble ray and ray casting approach.

Ethnographic studies of domestic environments have shown the fundamental roles that locations and context play in helping people understand and manage information in their homes. Yet it is not clear how this knowledge can be applied to the design of home technologies. For this reason, we present a case study in home technology design that uses the understandings gained from previous ethnographic studies on domestic locations to motivate the design of a home messaging system. Our prototype, called StickySpots, uses locations to embed technology in the social practices of the home. We then use this case study to reflect more generally on location-based design in the home.

Tangible interfaces are best viewed as an interacting collection of remotely-located distributed hardware and software components. The problem is that current physical user interface toolkits do not normally offer distributed systems capabilities, leaving developers with extra burdens such as device discovery and management, low-level hardware access, and networking. Our solution is Shared Phidgets, a toolkit for rapidly prototyping distributed physical interfaces. It offers programmers 3 ways to access and control remotely-located hardware, and the ability to create abstract devices by transforming, aggregating and even simulating device capabilities. Network communication and low-level access to device hardware are handled transparently, regardless of device location. ACM Classification: H.5.2 [Information Interfaces]: User interfaces – input devices and strategies, interaction styles, prototyping, user-centered design Keywords: Distributed physical user interfaces, Phidgets.

Teams that are geographically distributed often share information both in real-time and asynchronously. When such sharing is through groupware, change conflicts can arise when people pursue parallel and competing actions on the same information. This leads to problems in how the systems and its users maintain a consistent view of shared information across distance and time. We explore change awareness of conflicts in a three-dimensional distributed shared space. Our user study compares the use of visual feedback to an optimistic concurrency control strategy for both synchronous and asynchronous distributed groupware. Our feedback provides a means for synchronous users to recognize and resolve real-time changes, and for asynchronous users to view and resolve changes when switching from an offline to online mode of work. Results of our study suggest that the visual feedback serves as a useful feedthrough mechanism in the synchronous case, but that asynchronous users may be overwhelmed by the quantity of changes if they come online after many changes have been made.

Co-located collaborators often work over physical tabletops with rich geospatial information. Previous research shows that people use gestures and speech as they interact with artefacts on the table and communicate with one another. With the advent of large multi-touch surfaces, developers are now applying this knowledge to create appropriate technical innovations in digital table design. Yet they are limited by the difficulty of building a truly useful collaborative application from the ground up. In this paper, we circumvent this difficulty by: (a) building a multimodal speech and gesture engine around the Diamond Touch multi-user surface, and (b) wrapping existing, widely-used off-the-shelf single-user interactive spatial applications with a multimodal interface created from this engine. Through case studies of two quite different geospatial systems -- Google Earth and Warcraft III -- we show the new functionalities, feasibility and limitations of leveraging such single-user applications within a multi user, multimodal tabletop. This research informs the design of future multimodal tabletop applications that can exploit single-user software conveniently available in the market. We also contribute (1) a set of technical and behavioural affordances of multimodal interaction on a tabletop, and (2) lessons learnt from the limitations of single user applications.

Despite the availability of awareness servers and casual interaction systems, distributed groups still cannot maintain artifact awareness – the easy awareness of the documents, objects, and tools that other people are using – that is a natural part of co-located work environments. To address this deficiency, we designed an awareness tool that uses screen sharing to provide information about other people’s artifacts. People see others’ screens in miniature at the edge of their display, can selectively raise a larger view of that screen to get more detail, and can engage in remote pointing if desired. Initial experiences show that people use our tool for several purposes: to maintain awareness of what others are doing, to project a certain image of themselves, to monitor progress and coordinate joint tasks, to help determine when another person can be interrupted, and to engage in serendipitous conversation and collaboration. People have also been able to balance awareness with privacy, by using the privacy protection strategies built into our system: restricting what parts of the screen others can see, specifying update frequency, hiding image detail, and getting feedback of when screenshots are taken.

Most commercial software applications are designed for a single user using a keyboard/mouse over an upright monitor. Our interest is exploiting these systems so they work over a digital table. Mirroring what people do when working over traditional tables, we want to allow multiple people to interact naturally with the tabletop application and with each other via rich speech and hand gestures. In previous papers, we illustrated multi-user gesture and speech interaction on a digital table for geospatial applications -- Google Earth, Warcraft III and The Sims. In this paper, we describe our underlying architecture: GSI Demo. First, GSI Demo creates a run-time wrapper around existing single user applications: it accepts and translates speech and gestures from multiple people into a single stream of keyboard and mouse inputs recognized by the application. Second, it lets people use multimodal demonstration -- instead of programming -- to quickly map their own speech and gestures to these keyboard/mouse inputs. For example, continuous gestures are trained by saying "Computer, when I do [one finger gesture], you do [mouse drag]". Similarly, discrete speech commands can be trained by saying "Computer, when I say [layer bars], you do [keyboard and mouse macro]". The end result is that end users can rapidly transform single user commercial applications into a multi-user, multimodal digital tabletop system.

Always-on video provides rich awareness for distance-separated coworkers. Yet video can threaten privacy, especially when it captures telecommuters working at home. We evaluated video blurring, an image masking method long touted to balance privacy and awareness. Results show that video blurring is unable to balance privacy with awareness for risky situations. Reactions by participants suggest that other popular image masking techniques will be problematic as well. The design implication is that image masking techniques will not suffice for privacy protection in video-based telecommuting situations. Other context-aware privacy-protecting strategies are required, as illustrated in our prototype context-aware home media space.

The Community Bar is groupware supporting informal awareness and casual interaction for small social worlds: a group of people with a common purpose. Its conceptual design is primarily based on a comprehensive sociological theory called the Locales Framework, with extra details supplied by the Focus/Nimbus model of awareness. Design nuances are strongly influenced by observations and feedback supplied by a community who had been using both the Community Bar and its Notification Collage predecessor for a total of five years. As a consequence, Community Bar's design supports how communities of ad-hoc and long-standing groups are built and sustained within multiple locales: places that offer a group the site and means for maintaining awareness of one another and for rapidly moving into interaction. This includes a person's lightweight management of his or her membership in multiple locales, as well as ones varying engagement with the people and artefacts within them.

Many instant messenger (IM) clients let a person specify the identifying name that appears in another person's contact list. We have noticed that many people add extra information to this name as a way to broadcast information to their contacts. Twelve IM contact lists comprising 444 individuals were monitored over three weeks to observe how these individuals used and altered their display names. Almost half of them changed their display names at varying frequencies, where the new information fell into seventeen different categories of communication supplied to others. Three themes encompass these categories: Identification ("who am I"?), Information About Self ("this is what is going on with me") and Broadcast Message ("I am directing information to the community"). The design implication is that systems supporting person to person casual interaction, such as IM, should explicitly include facilities that allow people to broadcast these types of information to their community of contacts.

Video media spaces are an excellent crucible for the study of privacy. Their design affords opportunities for misuse, prompts ethical questions, and engenders grave concerns from both users and nonusers. Despite considerable discussion of the privacy problems uncovered in prior work, questions remain as to how to design a privacy-preserving video media space and how to evaluate its effect on privacy. The problem is more deeply rooted than this, however. Privacy is an enormous concept from which a large vocabulary of terms emerges. Disambiguating the meanings of and relationships between these terms facilitates understanding of the link between privacy and design. In this article, we draw from resources in environmental psychology and computer-supported cooperative work (CSCW) to build a broadly and deeply rooted vocabulary for privacy. We relate the vocabulary back to the real and hard problem of designing privacy-preserving video media spaces. In doing so, we facilitate analysis of the privacy-design relationship.

Single Display Groupware (SDG) lets multiple co-located people, each with their own input device, interact simultaneously over a single communal display. While SDG is beneficial, there is risk of interference: when two people are interacting in close proximity, one person can raise an interface component (such as a menu, dialog box, or movable palette) over another person's working area, thus obscuring and hindering the other's actions. Consequently, researchers have developed special purpose interaction components to mitigate interference techniques. Yet is interference common in practice? If not, then SDG versions of conventional interface components could prove more suitable. We hypothesize that collaborators spatially separate their activities to the extent that they partition their workspace into distinct areas when working on particular tasks, thus reducing the potential for interference. We tested this hypothesis by observing co-located people performing a set of collaborative drawing exercises in an SDG workspace, where we paid particular attention to the locations of their simultaneous interactions. We saw that spatial separation and partitioning occurred consistently and naturally across all participants, rarely requiring any verbal negotiation. Particular divisions of the space varied, influenced by seating position and task semantics. These results suggest that people naturally avoid interfering with one another by spatially separating their actions. This has design implications for SDG interaction techniques, especially in how conventional widgets can be adapted to an SDG setting.

Physical user interfaces are special purpose devices that can be situated in a real-world setting. Unlike general purpose computers, they are typically designed for particular contexts and uses. In this survey, I present an introductory tour of this new interface genre. First, I will summarize what they are by describing several design niches for these devices: ubiquitous computing, tangible media, foreground and ambient devices, collaborative devices, roomware, and physical controls. Examples will be plentiful, and will range from the playful, to the artistic, and to the serious. Second, I will introduce technologies that are suitable for software professionals who wish to prototype these physical user interfaces. The commercially available Phidgets (www.phidgets.com) are used as a case study of what is available and what can be done with them.

In order to support co-located collaboration, many researchers are now investigating how to effectively augment tabletops with electronic displays. As far back as 1988, orientation was recognized as a significant human factor issue that must be addressed by electronic tabletop designers. As with traditional tables, when people stand at different positions around a horizontal display they will be viewing the contents from different angles. One common solution to this problem is to have the software reorient objects so that any given individual can view them 'right way up.' Yet is this the best approach? If not, how do people actually use orientation on tables? To answer these questions, we conducted an observational study of collaborative activity on a traditional table. Our results show that the strategy of reorienting objects to a person's view is overly simplistic: while important, it is an incomplete view of how people exploit their ability to reorient objects. Orientation proves critical in how individuals comprehend information, how collaborators coordinate their actions, and how they mediate communication. The coordinating role of orientation is evident in how people establish personal and group spaces, and how they signal ownership of objects. In terms of communication, orientation is useful in initiating communicative exchanges and in continuing to speak to individuals about particular objects and work patterns as collaboration progresses. The three roles of orientation have significant implications for the design of tabletop software and the assessment of existing tabletop systems.

Researchers in Computer Supported Cooperative Work have recently developed discount evaluation methods for shared-workspace groupware. Most discount methods rely on some understanding of the context in which the groupware systems will be used, which means that evaluators need to model the tasks that groups will perform. However, existing task analysis schemes are not well suited to the needs of groupware evaluation: they either do not deal with collaboration issues, do not use an appropriate level of analysis for concrete assessment of usability in interfaces, or do not adequately represent the variability inherent in group work. To fill this gap, we have developed a new modeling technique called Collaboration Usability Analysis. CUA focuses on the teamwork that goes on in a group task rather than the taskwork. To enable closer links between the task representation and the groupware interface, CUA grounds each collaborative action in a set of group work primitives called the mechanics of collaboration . To represent the range of ways that a group task can be carried out, CUA allows variable paths through the execution of a task, and allows alternate paths and optional tasks to be modeled. CUA's main contribution is to provide evaluators with a framework in which they can simulate the realistic use of a groupware system and identify usability problems that are caused by the groupware interface.

Good real time groupware products are hard to develop, in part because evaluating their support for basic teamwork activities is difficult and costly. To address this problem, we are developing discount evaluation methods that look for groupware-specific usability problems. In a previous paper, we detailed a new set of usability heuristics that evaluators can use to inspect shared workspace groupware to see how they support teamwork. We wanted to determine whether the new heuristics could be integrated into a low-cost methodology that parallels Nielsen's traditional heuristic evaluation (HE). To this end, we examined 27 evaluations of two shared workspace groupware systems and analysed the inspectors' relative performance and variability. Similar to Nielsen's findings for traditional HE, individual inspectors discovered about a fifth of the total known teamwork problems, and that there was only modest overlap in the problems they found. Groups of three to five inspectors would report about 40-60% of the total known teamwork problems. These results suggest that heuristic evaluation using our groupware heuristics can be an effective and efficient method for identifying teamwork problems in shared workspace groupware systems.

When using today's productivity applications, people rely heavily on graphical controls (GUI widgets) as the way to invoke application functions and to obtain feedback. Yet we all know that certain controls can be difficult or tedious to find and use. As an alternative, a customizable physical interface lets an end-user easily bind a modest number of physical controls to similar graphical counterparts. The user can then use the physical control to invoke the corresponding graphical control's function, or to display its graphical state in a physical form. To show how customizable physical interfaces work, we present examples that illustrate how our combined phidgets® and widget tap packages are used to link existing application widgets to physical controls. While promising, our implementation prompts a number of issues relevant to others pursuing interface customization.

The Notification Collage (NC) is a groupware system where distributed and co-located colleagues comprising a small community post media elements onto a real-time collaborative surface that all members can see. Akin to collages of information found on public bulletin boards, NC randomly places incoming elements onto this surface. People can post assorted media: live video from desktop cameras; editable sticky notes; activity indicator; slide shows displaying a series of digital photos, snapshots of a person's digitial desktop, and Web page thumbnails. User experiences show that NC becomes a rich resource for awareness and collaboration. Community members indicate their presence to others by posting live video. They regularly act on this information by engaging in text and video conversations. Because all people can overhear conversations, these become active opportunities to join in. People also post items they believe will be interesting to others, such as desktop snapshots and vacation photos. Finally, people use NC somewhat differently when it is displayed on a large public screen than when it appears on a personal computer.

Single Display Groupware (SDG) supports face-to-face collaborators working over a single shared display, where all people have their own input device. Although SDG is simple in concept, there are surprisingly many problems in how interactions within SDG are managed. One problem is the potential for interference, where one person can raise an interface component (such as a menu or dialog box) in a way that hinders what another person is doing i.e., by obscuring another person’s working area that happens to be underneath the raised component. We propose transparent interface components as one possible solution to interference: while one person can raise and interact with the component, others can see through it and can continue to work underneath it. To test this concept, we first implemented a simple SDG game using both opaque and transparent SDG menus. Through a controlled experiment, we then analysed how interference affects peoples’performance across an opaque and transparent menu c ondition: a solo condition (where a person played alone) acts as our control. Our results show that the transparent menu did lessen the effect of interference, and that SDG players overwhelmingly preferred it to opaque menus.

Many researchers believe that groupware can only be evaluated by studying real collaborators in their real contexts, a process that tends to be expensive and time-consuming. Others believe that it is more practical to evaluate groupware through usability inspection methods. Deciding between these two approaches is difficult, because it is unclear how they compare in a real evaluation situation. To address this problem, we carried out a dual evaluation of a groupware system, with one evaluation applying user-based techniques, and the other using inspection methods. We compared the results from the two evaluations and concluded that, while the two methods have their own strengths, weaknesses, and trade-offs, they are complementary. Because the two methods found overlapping problems, we expect that they can be used in tandem to good effect, e.g., applying the discount method prior to a field study, with the expectation that the system deployed in the more expensive field study has a better chance of doing well because some pertinent usability problems will have already been addressed.

Physical widgets or phidgets are to physical user interfaces what widgets are to graphical user interfaces. Similar to widgets, phidgets abstract and package input and output devices: they hide implementation and construction details, they expose functionality through a well-defined API, and they have an (optional) on-screen interactive interface for displaying and controlling device state. Unlike widgets, phidgets also require: a connection manager to track how devices appear on-line; a way to link a software phidget with its physical counterpart; and a simulation mode to allow the programmer to develop, debug and test a physical interface even when no physical device is present. Our evaluation shows that everyday programmers using phidgets can rapidly develop physical interfaces.

Context is a dynamic construct. Although some contextual situations are fairly stable, discernable, and predictable, there are many others that are not. Similar looking contextual situations may actually differ dramatically, due perhaps to people's previous episodes of use, the state of their social interactions, their changing internal goals, and the nuances of local influences. The consequence is that, for all but simple cases, the designer of a context-aware application may find it difficult or even impossible to (a) enumerate the set of contextual states that may exist, (b) know what information could accurately determine a contextual state within that set, and (c) state what appropriate action should be taken from a particular state.

Video-based media spaces are designed to support casual interaction between intimate collaborators. Yet transmitting video is fraught with privacy concerns. Some researchers suggest that the video stream be filtered to mask out potentially sensitive information. While a variety of filtering techniques exist, they have not been evaluated for how well they safeguard privacy.

Collaborative interpretationoccurs when a group interprets and transforms a diverse set of information fragments into a coherent set of meaningful descriptions. This activity is characterized byemergence, where the participants' shared understanding develops gradually as they interact with each other and the source material. Our goal is to support collaborative interpretation by small, distributed groups. To achieve this, we first observed how face-to-face groups perform collaborative interpretation in a particular work context. We then synthesized design principles from two relevant areas: the key behaviors of people engaged in activities where emergence occurs, and how distributed groups work together over visual surfaces. We built and evaluated a system that supports a specific collaborative interpretation task. This system provides a large workspace and several objects that encourages emergence in interpretation. People manipulatecardsthat contain the raw information fragments. They reduce complexity by placing duplicate cards intopiles. They suggest groupings as they manipulate the spatial layout of cards and piles. They enrich spatial layouts throughnotes, textandfreehand annotations. They record their understanding of their final groupings asreportscontaining coherent descriptions.

Real-time collaboration in current distributed groupware workspaces is often an awkward and clumsy process.We hypothesize that better support for workspace awareness-the understanding of who is in the workspace, where they are working, and what they are doing-can improve the usability of these shared computational workspaces.We conducted an experiment that compared people's performance on two versions of a groupware interface.The interfaces used workspace miniatures to provide different levels of support for workspace awareness.The basic miniature showed information only about the local user, and the enhanced miniature showed the location and activity of other people in the workspace as well.We examined five aspects of groupware usability: task completion times, communication efficiency, the participants' perceived-effort, overall preference, and strategy use.In two of three task types tested, completion times were lower in the awareness-enhanced system, and in one task type, communication was more efficient.The additional awareness information also allowed people to use different and more effective strategies to complete the tasks.Participants greatly preferred the awareness-enhanced system.The study provides empirical evidence that support for workspace awareness improves the usability of groupware, and uncovers some of the reasons underlying this improvement.

Collaboration in current real-time groupware systems is often an awkward and clumsy process. We hypothesize that better support for workspace awareness can improve the usability of these shared computational workspaces. We conducted an experiment that compared people's performance on two versions of a groupware interface. The interfaces used workspace miniatures to provide different levels of support for workspace awareness. The basic miniature showed information only about the local user, and the enhanced miniature showed the location and activity of others in the workspace as well. In two of three task types tested, completion times were lower with increased awareness support, and in one task type, communication was more efficient. Participants also greatly preferred the awareness-enhanced system. The study provides empirical evidence of, and underlying reasons for, the value of supporting workspace awareness in groupware. Keywords workspace awareness, groupware, usability INTRODU...

Article Free Access Share on Design for individuals, design for groups: tradeoffs between power and workspace awareness Authors: Carl Gutwin Department of Computer Science, University of Saskatchewan, Saskatoon, SK, S7N 5A9, Canada Department of Computer Science, University of Saskatchewan, Saskatoon, SK, S7N 5A9, CanadaView Profile , Saul Greenberg Department of Computer Science, University of Calgary, Calgary, AB, T2N 1N4, Canada Department of Computer Science, University of Calgary, Calgary, AB, T2N 1N4, CanadaView Profile Authors Info & Claims CSCW '98: Proceedings of the 1998 ACM conference on Computer supported cooperative workNovember 1998 Pages 207–216https://doi.org/10.1145/289444.289495Published:01 November 1998Publication History 213citation2,057DownloadsMetricsTotal Citations213Total Downloads2,057Last 12 Months159Last 6 weeks15 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF

In this paper, we report on users ' revisitation patterns to World Wide Web (WWW) pages, and use the results to lay an empirical foundation for the design of history mechanisms in Web browsers. Through history, a user can return quickly to a previously visited page, possibly reducing the cognitive and physical overhead required to navigate to it from scratch. We analyzed 6 weeks of detailed usage data collected from 23 users of a commercial web browser. We found that 58 % of an individual’s pages are revisits, and that users continually add new Web pages into their repertoire of visited pages. People tend to revisit pages just visited, access only a few pages frequently, browse in very small clusters of related pages, and generate only short sequences of repeated URL paths. We compared different history mechanisms, and found that the stackbased prediction method prevalent in commercial browsers is inferior to the simpler approach of showing the last few recently visited URLs with duplicates removed. Other predictive approaches fare even better. These results suggest new approaches to managing history in browsers.

This paper describes our experiences implementing a component architecture for TeamWave WorkpIace, an integrated groupware environment using a rooms metaphor.The problem we faced was how to design the architecture to support rapid development of new embedded components.Our soIution, based on TcUTk and GroupKit, uses multiple interpreters and a shared window hierarchy.This proved effective in easing development complexity in TeamWave.We discuss some of the strategies we used, and identify the types of interactions between system components.The lessons learned in deveIoping this component model should be generally applicable to future integrated groupware systems in different environments.

Real time groupware systems are now moving away from strict view-sharing and towards relaxed “what-you-see-is-what-I-see” interfaces, where distributed participants in a real time session can view different parts of a shared visual workspace. As with strict view-sharing, people using relaxed-WYSIWIS require a sense of workspace awareness—the up-to-the-minute knowledge aobut another person's interactions with the shared workspace. The problem is deciding how to provide a user with an appropriate level of awareness of what other participants are doing when they are working in different areas of the workspace. In this video, we illustrate distortion oriented displays as a novel way of providing this awareness. These displays, which employ magnification lenses and fisheye view techniques, show global context and local detail within a single window, both peripheral and detailed awareness of other participants' actions. Three prototypes are presented as examples of groupware distortion-oriented displays. The head-up lens uses a see-through lens to show full-sized local detail in the foreground, and a miniature overview showing global context in the background. The offset lens employs a magnifying lens to show detail over a miniature overview. The fisheye text viewer provides people with detail of what everyone is doing through multiple focal points, one for each participant.

GroupWeb is a prototype browser that allows group members to visually share and navigate World Wide Web page in real time. Its groupware features include document and view slaving for synchronizing information sharing, telepointers for enacting gestures, and relaxed “what you see is what I see” views to handle display differences. A groupware text editor lets groups create and attach annotations to pages. An immediate application of GroupWeb is as a presentation tool for real time distance education and conferencing. The video illustrates GroupWeb and all its features.

Real-time groupware systems often let each participant control their own view into a shared workspace. However, when collaborators do not share the same view they lose their awareness about where and how others are interacting with the workspace artifacts. We have designed a number of add-on awareness windows that help people regain this awareness. Two general strategies and several variations are illustrated in this video that extend work done in a few other groupware systems. First, radar overviews shrink the entire workspace to fit within a single window. Awareness is indicated by overlaying the overview with boxes representing others' viewports, by telepointers that show where they are working, and by seeing changes to objects in the workspace as they are made. The workspace can be represented within the radar overview as a scaled miniature, by stylized objects, or by its semantic structure. Second, two types of detailed views show some or all of what another person can see, providing awareness of fine-grained details of others' actions.

Workspace awareness is knowledge about others' interaction with a shared workspace. Groupware systems provide only limited information about other participants, often compromising workspace awareness. This paper describes a usability study of several widgets designed to help maintain awareness in a groupware workspace. These widgets include a miniature view, a radar view, a multiuser scrollbar, a glance function, and a "what you see is what I do" view. The study examined the widgets' information content, how easily people could interpret them, and whether they were useful or distracting. Observations, questionnaires, and interviews indicate that the miniature and radar displays are useful and valuable for tasks involving spatial manipulation of artifacts. Keywords Workspace awareness, shared workspaces, usability study. INTRODUCTION People maintain an ongoing awareness of others in physical workspaces like whiteboards and tabletops, and they do this using everyday perceptual abilit...

Teams whose members are in close physical proximity often rely on team rooms to serve both as meeting places and repositories of the documents and artifacts that support their projects.TeamRooms is a groupware system that fills the role of a team room for groups whose members can work both co-located and at a distance.Facilities in TeamRooms allow team members to collaborate either in real-time or asynchronously, and to customize their shared electronic space with tools to suit their needs.Unlike many groupware systems, all TeamRooms documents and artifacts are fully persistent.

This article presents an overview of GroupKit, a groupware toolkit that lets developers build applications for synchronous and distributed computer-based conferencing. GroupKit was constructed from our belief that programming groupware should be only slightly harder than building functionally similar single-user systems. We have been able to significantly reduce the implementation complexity of groupware through the key features that comprise GroupKit. Aruntime infrastructureautomatically manages the creation, interconnection, and communications of the distributed processes that comprise conference sessions. A set ofgroupware programming abstractionsallows developers to control the behavior of distributed processes, to take action on state changes, and to share relevant data.Groupware widgetslet interface features of value to conference participants to be easily added to groupware applications.Session managers—interfaces that let people create and manage their meetings—are decoupled from groupware applications and are built by developers to accommodate the group's working style. Example GroupKit applications in a variety of domains have been implemented with only modest effort.

Many information structures are represented as two-dimensional networks (connected graphs) of links and nodes. Because these network tend to be large and quite complex, people often perfer to view part or all of the network at varying levels of detail. Hierarchical clustering provides a framework for viewing the network at different levels of detail by superimposing a hierarchy on it. Nodes are grouped into clusters, and clusters are themselves place into other clusters. Users can then navigate these clusters until an appropiate level of detail is reached. This article describes an experiment comparing two methods for viewing hierarchically clustered networks. Traditional full-zoom techniques provide details of only the current level of the hierarchy. In contrast, fisheye views, generated by the “variable-zoom” algorithm described in this article, provide information about higher levels as well. Subjects using both viewing methods were given problem-solving tasks requiring them to navigate a network, in this case, a simulated telephone system, and to reroute links in it. Results suggest that the greater context provided by fisheye views significantly improved user performance. Users were quicker to complete their task and made fewer unnecessary navigational steps through the hierarchy. This validation of fisheye views in important for designers of interfaces to complicated monitoring systems, such as control rooms for supervisory control and data acquistion systems, where efficient human performance is often critical. However, control room operators remained concerned about the size and visibility tradeoffs between the fine room operators remained concerned about the size and visibility tradeoffs between the fine detail provided by full-zoom techniques and the global context supplied by fisheye views. Specific interface feaures are required to reconcile the differences.

This paper exposes the concurrency control problem in groupware when it is implemented as a distributed system. Traditional concurrency control methods cannot be applied directly to groupware because system interactions include people as well as computers. Methods, such as locking, serialization, and their degree of optimism, are shown to have quite different impacts on the interface and how operations are displayed and perceived by group members. The paper considers both human and technical considerations that designers should ponder before choosing a particular concurrency control method. It also reviews our work-in-progress designing and implementing a library of concurrency schemes in GROUPKIT, a groupware toolkit.

This paper presents our approach to the design of groupware toolkits for real-time work, and how the design is instantiated in our toolkit, GROUPKIT.The design is based on both the technical underpinnings necessary for real-time groupware, and on user-centered features identified by existing CSCW human factors work.We also present three strategies for building GROUPKIT's components.First, an extendible, object-oriented run-time architecture supports managing distributed processes and the communication between them.Second, transparent overlays offer a convenient method for adding general components to various groupware applications, for example supporting gestures via multiple cursors and annotation via sketching.Third, open protocols allow the groupware designer to create a wide range of interface and interaction policies, accommodating group differences in areas such as conference registration and floor control.

Groupware designers are now developing multi-user equivalents of popular paint and draw applications. Their job is not an easy one. First, human factors issues peculiar to group interaction appear that, if ignored, seriously limit the usability of the group tool. Second, implementation is fraught with considerable technical hurdles. This paper describes the human and technical factors that have been met and handled by researchers and implementors of group drawing tools. We emphasize our own experiences building four systems supporting remote real time group interaction: GroupSketch and XGroupSketch, both multi-user sketchpads; GroupDraw, a prototype object-based multi-user drawing package, and GroupKit, a groupware toolkit. On the human factors side, we summarize empirically-derived design principles that we believe are critical to building useful and usable collaborative drawing tools. On the implementation side, we describe our experiences with replicated versus centralized architectures, schemes for participant registration, multiple cursors, network requirements, and the structure of the drawing primitives. A brief survey of other approaches to group drawing is also included.

Several striking characteristics of how often people repeat their actions on interactive systems are abstracted from usage data gleaned from many users of different classes over a period of months. Reformulated as empirically-based general principles, these provide design guidelines for history mechanisms specifically and modern user interfaces generally. Particular attention is paid to the repetition of command lines, and to the probability distribution of the next line given a sequential “history list” of previous ones. Several ways are examined of conditioning this distribution to enhance predictive power. A brief case study of actual use of a widely-used history system is also included.