Model mismatch analysis: towards a deeper explanation of users' usability problems

An evaluation method is proposed based on walkthrough analysis coupled with a taxonomic analysis of observed problems and causes of usability error. The model mismatch method identifies usability design flaws and missing requirements from user errors. The method is tested with a comparative evaluation of two information retrieval products. Different profiles of usability and requirements problems were found for the two products, even though their overall performance was similar.