Series
Doctor of Philosophy with a Major in Computer Science

Series Type
Degree Series
Description
Associated Organization(s)
Associated Organization(s)

Publication Search Results

Now showing 1 - 4 of 4
  • Item
    Understanding the social navigation user experience
    (Georgia Institute of Technology, 2009-07-06) Goecks, Jeremy
    A social navigation system collects data from its users--its community--about what they are doing, their opinions, and their decisions, aggregates this data, and provides the aggregated data--community data--back to individuals so that they can use it to guide behavior and decisions. In this thesis, I document my investigation of the user experience for social navigation systems that employ activity data. I make three contributions in this thesis. First, I synthesize social navigation systems research with research in social influence, advice-taking, and informational cascades to construct hypotheses about the social navigation user experience. These hypotheses posit that community data from a social navigation system exerts informational influence on users, that users egocentrically discount community data, that herding in social navigation systems can be characterized as informational cascades, and that the size and unanimity of the community data correspond to the strength of the community data's influence. The second contribution of this thesis is an experiment that evaluates the hypotheses about the social navigation user experience; this experiment investigated how a social navigation system can support online charitable giving decisions. The experiment's results support the majority of the hypotheses about the social navigation user experience and provide mixed evidence for the other hypotheses. The implications that arise from the experiment's findings compromise the final contribution of this thesis. These implications concern improving the design of social navigation systems and developing a general framework for evaluating the social influence of social navigation systems.
  • Item
    Exploring user interface challenges in supporting activity-based knowledge work practices
    (Georgia Institute of Technology, 2008-05-19) Voida, Stephen
    The venerable desktop metaphor is beginning to show signs of strain in supporting modern knowledge work. Traditional desktop systems were not designed to support the sheer number of simultaneous windows, information resources, and collaborative contexts that have become commonplace in contemporary knowledge work. Even though the desktop has been slow to evolve, knowledge workers still consistently manage multiple tasks, collaborate effectively among colleagues or clients, and manipulate information most relevant to their current task by leveraging the spatial organization of their work area. The potential exists for desktop workspaces to better support these knowledge work practices by leveraging the unifying construct of activity. Semantically-meaningful activities, conceptualized as a collection of tools (applications, documents, and other resources) within a social and organizational context, offer an alternative orientation for the desktop experience that more closely corresponds to knowledge workers' objectives and goals. In this research, I unpack some of the foundational assumptions of desktop interface design and propose an activity-centered model for organizing the desktop interface based on empirical observations of real-world knowledge work practice, theoretical understandings of cognition and activity, and my own experiences in developing two prototype systems for extending the desktop to support knowledge work. I formalize this analysis in a series of key challenges for the research and development of activity-based systems. In response to these challenges, I present the design and implementation of a third research prototype, the Giornata system, that emphasizes activity as a primary organizing principle in GUI-based interaction, information organization, and collaboration. I conclude with two evaluations of the system. First, I present findings from a longitudinal deployment of the system among a small group of representative knowledge workers; this deployment constitutes one of the first studies of how activity-based systems are adopted and appropriated in a real-world context. Second, I provide an assessment of the technologies that enable and those that pose barriers to the development of activity-based computing systems.
  • Item
    Set-Based User Interaction
    (Georgia Institute of Technology, 2005-07-13) Terry, Michael Andrew
    This work demonstrates specific ways that the design of computer user interfaces can influence how individuals structure the problem solving process. In particular, an observational study of expert users of an image manipulation application indicates that current user interfaces make it difficult to explore sets of alternatives in parallel, despite this being a common problem solving practice. As a consequence, individuals tend to engage in highly linear problem solving processes. To address this problem, this work introduces the concept of a set-based interface, or an interface that facilitates the generation, manipulation, evaluation, and management of sets of alternative solutions. The concepts of a set-based interface are demonstrated in two tools, Side Views and Parallel Pies, both designed for use in the domain of image manipulation. Side Views automatically generates sets of previews for one or more commands and their parameters, enabling side-by-side comparison of alternatives. Parallel Pies streamlines the process of forking, or the act of creating new, standalone alternatives, and provides a visualization to evaluate results. Two controlled laboratory studies and a third think-aloud study reveal that these tools lead to users more broadly exploring the solution space and developing more optimal solutions for some types of tasks. These studies also show that the ability to broadly explore can initially be overused, adversely affecting solution quality if not enough time is spent maturing a single solution instance. This enthusiastic use of exploration tools is especially notable because such features are entirely optional to developing a solution. As such, these results suggest the need to further research ways user interfaces can support individuals in rapidly generating sets of alternative solutions. To support future research in this direction, this work contributes a set of metrics for quantifying breadth and depth of exploration; backtracking; and dead-ends in the problem solving process. A visualization called a process diagram aids in communicating these concepts.
  • Item
    Exploring the Design and Use of Forecasting Groupware Applications with an Augmented Shared Calendar
    (Georgia Institute of Technology, 2005-04-19) Tullio, Joseph
    Changes in work, along with improvements in techniques to statistically model uncertainty, have resulted in a class of groupware tools able to forecast the activities and/or attentional state of their users. This thesis represents an exploration into the design, development, and use of one such system. I describe the design and development of a groupware calendar system called Augur that is augmented with the ability to predict the attendance of its users. Using Bayesian networks, Augur models the uncertain problem of event attendance, drawing inferences based on the attributes of calendar events as well as a history of attendance provided by each user. This system was deployed to an academic workgroup and studied over the course of a semester. To more deeply explore the social implications of Augur and systems like it, I conducted a structured privacy analysis of Augur to examine the vulnerabilities inherent in this type of forecasting groupware system. I present an architecture, user interface, and probabilistic model for Augur. This work also addresses the feasibility of such a system and the challenges faced when deploying it to an academic workgroup. I also report on an exploration of the systems use by individuals, its effects on communication within working relationships, and its effectiveness with respect to the presence of domestic calendars. Finally, I present a set of implications for the workplace social environment with the introduction of Augur. Specifically, I show how the integrity of predictions generated by Augur can have consequences for the privacy of users and their representations through the shared calendar. Overall, this thesis is presented as an early exploration into the potential for a new class of forecasting groupware applications. It offers guidance and lessons learned for both designers and researchers seeking to work in this area. It also presents a complete calendar application as an example for building and studying such systems.