Usability Reasoning Using OWL 2 RL

How users experience a web-site's usability is mostly subjective. There is an ISO standard adressing usability requirements (EN ISO 9241-11). However, its propositions are kept rather general and focus strongly on individual usage situations. Nevertheless, there are usability critera for websites that can be considered negative, e.g. bad contrast, a high readability index, or discrepancies between an expected user behavior and the users' actual behavior. Our system — AbRUPt — is able to capture a large number of such criteria automatically. By converting, modeling and developing a rule base in the semantic ontology language OWL 2 RL, a system is created that allows automated reasoning for potential web usability problems. This rule base will be presented in this paper.