On the Vague Modelling of Web Page Characteristics Regarding Usability

Vagueness is an inherent property of man-machine systems associated with some perceptual and cognitive characteristics of human information processing, as pointed out by Karwowski and other researchers. More concretely, some perceivable characteristics of interface designs, including sizes and quantities, are usually perceived by humans as vague categories that result in imprecise guidelines for interface usability. In this paper, we describe how such categories — in the specific case of the Web — can be modelled as fuzzy sets by using conventional membership function elicitation procedures, using Web page length and number of links as case studies. The resulting fuzzy sets can then be used for automated usability analysis processes using fuzzy rules to formalize vague guidelines.