Model-based heuristic evaluation of hypermedia usability

This paper presents a systematic approach to the heuristic evaluation of hypermedia that specifically addresses the peculiar features of this class of systems. We propose a set of hypermedia-specific usability attributes and define general "patterns of evaluation activities" called abstract tasks that can be performed by usability experts to check such attributes systematically. The usage of abstract tasks makes application inspection more effective, since it guides the work of evaluators and supports standardization across different evaluators. Our approach is model-based since we use a hypermedia design model (HDM) to identify the constituents of an application that represent the "focus of interest" for the evaluation, to decompose general usability principles into hypermedia-specific attributes, and finally to formulate abstract tasks in a precise way. To show the effectiveness of our method, we discuss the most significant usability problems discovered in eight commercially available hypermedia CD-ROM's.