We report on a diary study of the activities of information workers aimed at characterizing how people interleave multiple tasks amidst interruptions. The week-long study revealed the type and complexity of activities performed, the nature of the interruptions experienced, and the difficulty of shifting among numerous tasks. We present key findings from the diary study and discuss implications of the findings. Finally, we describe promising directions in the design of software tools for task management, motivated by the findings.

This paper presents results of a long-term client-side Web usage study, updating previous studies that range in age from five to ten years. We focus on three aspects of Web navigation: changes in the distribution of navigation actions, speed of navigation and within-page navigation. “Navigation actions ” corresponding to users ’ individual page requests are discussed by type. We reconfirm links to be the most important navigation element, while backtracking has lost more than half of its previously reported share and form submission has become far more common. Changes of the Web and the browser interfaces are candidates for causing these changes. Analyzing the time users stayed on pages, we confirm Web navigation to be a rapidly interactive activity. A breakdown of page characteristics shows that users often do not take the time to read the available text or consider all links. The performance of the Web is analyzed and reassessed against the resulting requirements. Finally, habits of within-page navigation are presented. Although most selected hyperlinks are located in the top left corner of the screen, in nearly a quarter of all cases people choose links that require scrolling. We analyzed the available browser real estate to gain insights for the design of non-scrolling Web pages.

This paper presents results of an extensive long-term clickstream study of Web browser usage. Focusing on character and challenges of page revisitation, previous findings from seven to thirteen years ago are updated. The term page revisit had to be differentiated, since the recurrence rate—the key measure for the share of page revisits—turns out to strongly depend on interpretation. We identify different types of revisitation that allow assessing the quality of current user support and developing concepts for new tools. Individual navigation strategies differ dramatically and are strongly influenced by personal habits and type of site visited. Based on user action logs and interviews, we distinguished short-term revisits (backtrack or undo) from medium-term (re-utilize or observe) and long-term revisits (rediscover). We analyze current problems and provide suggestions for improving support for different revisitation types.

Information workers often have to balance many tasks and interruptions. In this work, we explore peripheral display techniques that improve multitasking efficiency by helping users maintain task flow, know when to resume tasks, and more easily reacquire tasks. Specifically, we compare two types of abstraction that provide different task information: semantic content extraction, which displays only the most relevant content in a window, and change detection, which signals when a change has occurred in a window (all designed as modifications to Scalable Fabric [17]). Results from our user study suggest that semantic content extraction improves multitasking performance more so than either change detection or our base case of scaling. Results also show that semantic content extraction provides significant benefits to task flow, resumption timing, and reacquisition. We discuss the implication of these findings on the design of peripheral interfaces that support multitasking. Author Keywords: Information visualization, peripheral displays, abstraction, multitasking

1 Personal Information Management (PIM) is an activity in which an individual stores his\her personal information items in order to retrieve them later on. In a former article, we suggested the user-subjective approach, a theoretical approach proposing design principles with which PIM systems can systematically use subjective attributes of information items. In this consecutive paper, we report on a study that tested the approach by exploring the use of subjective attributes (project, importance and context) in current PIM systems, and its dependence on design characteristics. Participants were 84 personal computer users. Tools included a questionnaire (N=84), a semi-structured interview that was transcribed and analyzed (N=20), and screen captures taken from this sub-sample. Results indicate that participants tended to use subjective attributes when the design encouraged them to, however, when the design discouraged such use, they either found their own alternative ways to use them or refrained from using them altogether. This constitutes evidence in support of the user-subjective approach as it

We report on a study of how people look for information within email, files, and the Web. When locating a document or searching for a specific answer, people relied on their contextual knowledge of their information target to help them find it, often associating the target with a specific document. They appeared to prefer to use this contextual information as a guide in navigating locally in small steps to the desired document rather than directly jumping to their target. We found this behavior was especially true for people with unstructured information organization. We discuss the implications of our findings for the design of personal information management tools.

In this paper we investigate information scraps – personal information where content has been scribbled on Post-it notes, scrawled on the corners of sheets of paper, stuck in our pockets, sent in e-mail messages to ourselves, and stashed in miscellaneous digital text files. Information scraps encode information ranging from ideas and sketches to notes, reminders, shipment tracking numbers, driving directions, and even poetry. Although information scraps are ubiquitous, we have much still to learn about these loose forms of information practice. Why do we keep information scraps outside of our traditional PIM applications? What role do information scraps play in our overall information practice? How might PIM applications be better designed to accommodate and support information scraps ’ creation, manipulation and retrieval? We pursued these questions by studying the information scrap practices of 27 knowledge workers at five organizations. Our observations shed light on information scraps ’ content, form, media and location. From this data, we elaborate on the typical information scrap lifecycle, and identify common roles that information scraps play: temporary storage, archiving, work-in-progress, reminding, and management of unusual data. These roles suggest a set of unmet design needs in current PIM tools: lightweight entry, unconstrained content, flexible use and adaptability, visibility, and mobility.

Conducting research using the web is often an iterative process of collecting, comparing and contrasting information. Not surprisingly, web-based research tasks habitually span multiple web sessions and involve considerable web page revisitation. Such tasks are not only carried out by researchers, but also by casual web users who, for example, plan vacations and large purchases. Despite the prominence of this activity among web users, existing tools support it poorly. We propose an alternative approach, whereby web-based research tasks are facilitated by a web workspace which represents collected URLs with web page thumbnails. A prototype of our design was developed and studied in an evaluation with 12 participants. Each of the participants adopted the workspace approach instinctively: the workspace was used for web page revisitation, web page comparison, collection overview, cross-session task continuation, and continuous task focus.

In the past decade, the World Wide Web has been subject to dramatic changes. Web sites have evolved from static information resources to dynamic and interactive applications that are used for a broad scope of activities on a daily basis. To examine the consequences of these changes on user behavior, we conducted a long-term client-side Web usage study with twenty-five participants. This report presents results of this study and compares the user behavior with previous long-term browser usage studies, which range in age from seven to thirteen years. Based on the empirical data and the interview results, various implications for the interface design of browsers and Web sites are discussed. A major finding is the decreasing prominence of backtracking in Web navigation. This can largely be attributed to the increasing importance of dynamic, service-oriented Web sites. Users do not navigate on these sites searching for information, but rather interact with an online application to complete certain tasks. Furthermore, the usage of multiple windows and tabs has partly replaced back button usage, posing new challenges for user orientation and backtracking. We found that Web browsing is a rapid activity even for pages with substantial content, which calls for page designs that allow for cursory reading. Click maps provide additional information on how users interact with the Web on page level. Finally, substantial differences were observed between users, and characteristic usage patterns for different types of Web sites emphasize the need for more adaptive and customizable Web browsers.

Web search engines face an extremely heterogeneous user population from web novices to highly skilled experts. Currently, the search strategies of the experienced web searchers are largely unknown and this paper addresses this issue by an observational study. Seven computer scientists were observed during and interviewed after performing their own work-related web search tasks. The observations indicated that experts have effective means for enhancing the searching, such as: using multiple search terms and operators, frequent query editing, using multiple windows, versatile result saving, and using the 'Find ' functionality. On the other hand, even the experts had misconceptions about the default operator and the ordering of the returned documents. Based on the results we suggest that search user interfaces should: 1) suggest alternative search terms, 2) explain search operators in natural language, 3) provide search history, and 4) facilitate users ’ orientation to the results. The suggestions are formulated as concrete solutions in a prototype user interface. The aim is to transfer the advanced strategies to the disposal of all users, not just experts.