Figure 3 . Comparison of number of unique problem types identified in Heuristic and UPI methods.
The UAF provides a model-based framework for examining usability issues in the context of user action. From the UAF, we are able to map to various usability tools, including the UPI for prediction of usability problems. We expect that the UAF, and associated mappings, will provide usability professionals with comprehensive tools to conduct more efficient and effective usability evaluations through an easily understood framework, a complete way to understand problems, and built-in links to possible design solutions.
This work has benefited from comments and suggestions provided by José Castillo, Deborah Hix, Steve Belz, and Faith McCreary. This research was supported by the Virginia Center for Innovative Technology and the CrossMedia Networks Corporation. MyInBox is a registered trademark of the CrossMedia Networks Corporation.
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