TRACKING THE EFFECTIVENESS OF USABILITY EVALUATION METHODS

We present a case study that tracks usability problems predicted with six usability evaluation methods (claims analysis, cognitive walkthrou gh, GOMS, heuristic evaluation, user action notation, and simply readi ng the specification) through a development process. We assess the met hod's predictive power by comparing the predictions to the results of user tests. We assess the method's persuasive power by seeing how many problems led to changes in the implemented code. We assess design-cha nge effectiveness by user testing the resulting new versions of the sy stem. We conclude that predictive methods are not as effective as the HCI field would like and discuss directions for future research.