This paper sheds light on gaps and discrepancies between the experiences afforded by analog pens and their digital counterparts. Despite the long history (and recent renaissance) of digital pens, the literature still lacks a comprehensive survey of what types of marks people make and what motivates them to use ink-both analog and digital in daily life. To capture the diversity of inking behaviors and tease out the unique affordances of pen-and ink, we conducted a diary study with 26 participants from diverse backgrounds. From analysis of 493 diary entries we identified 8 analog pen-and-ink activities, and 9 affordances of pens. We contextualized and contrasted these findings using a survey with 1,633 respondents and a follow-up diary study with 30 participants, observing digital pens. Our analysis reveals gaps and research opportunities based on pen affordances not yet fully explored in the literature.

Teamwork in software engineering is time-consuming and problematic. In this paper, we explore how to better support developers' collaboration in teamwork, focusing on the software implementation phase happening in the integrated development environment (IDE). Conducting a qualitative investigation, we learn that developers' teamwork needs mostly regard coordination, rather than concurrent work on the same (sub)task, and that developers successfully deal with scenarios considered problematic in literature, but they have problems dealing with breaking changes made by peers on the same project. We derive implications and recommendations. Based on one of the latter, we analyze the current IDE support for receiving code changes, finding that historical information is neither visible nor easily accessible. Consequently, we devise and qualitatively evaluate BELLEVUE, the design of an IDE extension to make received changes always visible and code history accessible in the editor.

While many studies have investigated the challenges that developers face in finding and using API documentation, few have considered the role of developers' conceptual knowledge in these tasks. We designed a study in which developers were asked to explore the feasibility of two requirements concerning networking protocols and application platforms that most participants were unfamiliar with, observing the effect that a lack of conceptual knowledge had on their use of documentation. Our results show that without conceptual knowledge, developers struggled to formulate effective queries and to evaluate the relevance or meaning of content they found. Our results suggest that API documentation should not only include detailed examples of API use, but also thorough introductions to the concepts, standards, and ideas manifested in an API's data structures and functionality.

Programming has recently become more common among ordinary end users of computer systems. We believe that these end-user programmers are not just coders but also designers, in that they interlace making design decisions with coding rather than treating them as two separate phases. To better understand and provide support for the programming and design needs of end users, we propose a design theory-based approach to look at end-user programming. Toward this end, we conducted a think-aloud study with ten end users creating a web mashup. By analyzing users' verbal and behavioral data using Schon's reflection-in-action design model and the notion of ideations from creativity literature, we discovered insights into end-user programmers' problem-solving attempts, successes, and obstacles, with accompanying implications for the design of end-user programming environments for mashups. The contribution of our work is three-fold: 1) the methodology of using a design lens to view programming, 2) evidence, through insights gained, of the usefulness of this approach, and 3) the implications themselves.

The recent emphasis on sustainability has made consumers more aware of their responsibility for saving resources, in particular, electricity. Consumers can better understand how to save electricity by gaining awareness of their consumption beyond the typical monthly bill. We conducted a study to understand consumers' awareness of energy consumption in the home and to determine their requirements for an interactive, always-on interface for exploring data to gain awareness of home energy consumption. In this paper, we describe a three-stage approach to supporting electricity conservation routines: raise awareness, inform complex changes, and maintain sustainable routines. We then present the findings from our study to support design implications for energy consumption feedback interfaces.

Many machine-learning algorithms learn rules of behavior from individual end users, such as task-oriented desktop organizers and handwriting recognizers. These rules form a “program” that tells the computer what to do when future inputs arrive. Little research has explored how an end user can debug these programs when they make mistakes. We present our progress toward enabling end users to debug these learned programs via a Natural Programming methodology. We began with a formative study exploring how users reason about and correct a text-classification program. From the results, we derived and prototyped a concept based on “explanatory debugging”, then empirically evaluated it. Our results contribute methods for exposing a learned program's logic to end users and for eliciting user corrections to improve the program's predictions.

Navigating in large geometric spaces-such as maps, social networks, or long documents-typically requires a sequence of pan and zoom actions. However, this strategy is often ineffective and cumbersome, especially when trying to study and compare several distant objects. We propose a new distortion technique that folds the intervening space to guarantee visibility of multiple focus regions. The folds themselves show contextual information and support unfolding and paging interactions. We conducted a study comparing the space-folding technique to existing approaches and found that participants performed significantly better with the new technique. We also describe how to implement this distortion technique and give an in-depth case study on how to apply it to the visualization of large-scale 1D time-series data.

Participatory Design is a design approach that provides a popular set of techniques for designing interactive systems in collaboration with end-users. Technology probes are one of such techniques, developed recently to encourage users' engagement with design ideas while capturing interaction. In this paper, we describe a technology probe called Zebra, which aimed at exploring the design of an observation tool for fieldwork with busy professionals. We deployed Zebra in the coffee room of our lab and observed researchers' reactions to the proposed concepts it embodied, both as researchers and as participants. We found that participants engaged with the probe in ways ranging from playful performances, through to abandoning the social space. Based on analysis of the collected qualitative and quantitative data, we present our reflections on the Zebra probe, how it eased the burden of engagement in the design process, and helped us better understand the potential of the observation tool for participatory design with busy professionals.

Interaction and navigation in large geometric spaces typically require a sequence of pan and zoom actions. This strategy is often ineffective and cumbersome, especially when trying to study several distant objects. We propose a new distortion technique that folds the intervening space to guarantee visibility of multiple focus regions. The folds themselves show contextual information and support unfolding and paging interactions. Compared to previous work, our method provides more context and distance awareness. We conducted a study comparing the space-folding technique to existing approaches, and found that participants performed significantly better with the new technique.