Towards visual analysis of usability test logs using task models

Abstract

In this paper we discuss techniques on how task models can enhance visualization of the usability test log. Evaluation of the usability tests is a traditional method in user centered design. It is a part of the methodology for design of usable products. We developed a tool for visualization of usability logs that uses the hierarchical structure of the task models to group and visualize observers' annotations. This way of visualization is very natural and allows investigation of the test dynamics and comparison of participant's behavior in various parts of the test. We also describe methods of visualization of multiple logs that allow for comparison of the test results between participants. For that purpose we present a new visualization method based on alignment of the visual representations of tasks, where binding between the task model and the log visualization is used. Finally, we present an evaluation of our tool on two usability tests, which were conducted in our laboratory and we discuss observed findings. © Springer-Verlag Berlin Heidelberg 2007.