Zhiwei Guan

What are you looking for?: an eye-tracking study of information usage in web search

Web search services are among the most heavily used applications on the World Wide Web. Perhaps because search is used in such a huge variety of tasks and contexts, the user interface must strike a careful balance to meet all user needs. We describe a study that used eye tracking methodologies to explore the effects of changes in the presentation of search results. We found that adding information to the contextual snippet significantly improved performance for informational tasks but degraded performance for navigational tasks. We discuss possible reasons for this difference and the design implications for better presentation of search results.

Experimental analysis of mode switching techniques in pen-based user interfaces

Inking and gesturing are two central tasks in pen-based user interfaces. Switching between modes for entry of uninterpreted ink and entry of gestures is required by many pen-based user interfaces. Without an appropriate mode switching technique, pen-based interactions in such situations may be inefficient and cumbersome. In this paper, we investigate five techniques for switching between ink and gesture modes in pen interfaces, including a pen-pressure based mode switching technique that allows implicit mode transition. A quantitative experimental study was conducted to evaluate the performance of these techniques. The results suggest that pressing a button with the non-preferred hand offers the fastest performance, while the technique of holding the pen still is significantly slower and more prone to error than the other techniques. Pressure, while promising, did not perform as well as the non-preferred hand button with our current implementation.

Does think aloud work?: how do we know?

The think aloud method is widely used in usability research to collect users reports of the experience of interacting with a design so that usability evaluators can find the underlying usability problems. However, concerns remain about the validity and usefulness of think aloud in usability studies. In this panel we will present current studies of the think aloud method, examine and question its usage in the field, discuss the possible pitfalls that may threaten the validity of the method, and provide comments/suggestions on the application of the method. Panel participants will discuss results drawn from both applied research and basic research.We believe that this panel discussion will be useful for HCI designers and usability practitioners in that it will acquaint them with concerns that people have about the think aloud method and provide them with suggestions for improved use of the method. For HCI or usability researchers, this panel discussion will address the importance of formally investigating currently used or newly designed usability methods.

I thought this was going to be a waste of time:How portfolio construction can support student learning from project-based experiences

In this work, we sought to understand ways that students experienced a small-scale portfolio assignment provided to them as an opportunity to reflect on their experiences in a project-based class. This work was motivated by research in various instructional contexts showing that portfolio construction results in important learning outcomes. We wanted to see if such findings would extend to project-based learning situations in engineering. In addition, our research was motivated by the need to better understand specific portfolio assignments in terms of the effort required of students, the extent to which students value such assignments, and the ways in which students’ overall experiences differ in terms of learning, effort, and value. To address these issues, we interviewed thirteen students who completed a portfolio assignment as a culminating activity for a project-based manufacturing class. We selected these students because their individual responses to a screening survey suggested that they had very different experiences with the portfolio assignment. We then conducted open-ended interviews with the students in order to better understand their experiences. In this paper, we show how the themes of epistemically different, manageably effortful, and ultimately valuable can be used to understand three ways of experiencing the assignment (as a significant experience, a muted experience, and a limited experience). This work provides practical information to educators interested in supporting reflection while also contributing to the scholarship on how portfolios support learning from experience.

User-centered design of course-based portfolios for mechanical engineering student learning

One challenge for engineering educators is to design appropriate educational curricula that address both students’ needs and educators’ expectations. It is therefore important for the engineering education community to think about how to include students and faculty into the assignment design process. In this paper we discuss our use of user-centered design (UCD) principles, including early focus on users, empirical measurements, and iteration design, to design course-based portfolio (CBP) assignments for mechanical engineering students. To support the assignment design decisions, we collected early information about mechanical engineering students’ learning needs and educators’ expectations. Based on the design considerations that we identified for portfolio design, the CBP assignment is designed to ask students build a persuasive document and identify the connections between the course and mechanical engineering discipline. We measured our design by piloting the assignment with students and getting feedback from faculty in the Mechanical Engineering Department; this feedback reflects the effectiveness of the CBP and leads to design iterations and tradeoffs. We also identified several students’ learning opportunities and formed these opportunities into hypotheses to evaluate the impacts of course-based portfolios on students learning in the next formal study. This research demonstrates a successful practice of using user-centered design principles to design a course-based portfolio assignment for mechanical engineering students.Copyright

Beyond current user research: designing methods for new users, technologies, and design processes

With the rapid diversification of computing technologies, user researchers often encounter new applications, new users and scenarios of use, and even new design processes that require new research approaches. (For instance, how do you assess the usability of a roving, multi-user, activity-based system? Or how do you assess a device intended to support a social network?) In this workshop we will examine case studies from user researchers who have modified a classic user research technique or created a new technique to meet the exigencies of such challenges. The workshop is organized around three aspects of methods design: the impetus for creating the new or modified method, the challenges of implementing the method, and the impact of the innovation on the design or design process.