title: Using a fuzzy comprehensive evaluation method to determine product usability: A proposed theoretical framework.
abstract: BACKGROUND
  In order to compare existing usability data to ideal goals or to that for other products, usability practitioners have tried to develop a framework for deriving an integrated metric. However, most current usability methods with this aim rely heavily on human judgment about the various attributes of a product, but often fail to take into account of the inherent uncertainties in these judgments in the evaluation process.
  
  
  OBJECTIVE
  This paper presents a universal method of usability evaluation by combining the analytic hierarchical process (AHP) and the fuzzy evaluation method. By integrating multiple sources of uncertain information during product usability evaluation, the method proposed here aims to derive an index that is structured hierarchically in terms of the three usability components of effectiveness, efficiency, and user satisfaction of a product.
  
  
  METHODS
  With consideration of the theoretical basis of fuzzy evaluation, a two-layer comprehensive evaluation index was first constructed. After the membership functions were determined by an expert panel, the evaluation appraisals were computed by using the fuzzy comprehensive evaluation technique model to characterize fuzzy human judgments. Then with the use of AHP, the weights of usability components were elicited from these experts.
  
  
  CONCLUSIONS
  Compared to traditional usability evaluation methods, the major strength of the fuzzy method is that it captures the fuzziness and uncertainties in human judgments and provides an integrated framework that combines the vague judgments from multiple stages of a product evaluation process.
authors.affiliation: School of Economics and Management, Beihang University, Beijing, P. R. China.
authors.forename: Ronggang
authors.initials: R
authors.lastname: Zhou
authors.affiliation: Department of Systems Engineering and Engineering Management, City University of Hong Kong, Hong Kong, P. R. China.
authors.forename: Alan H S
authors.initials: AH
authors.lastname: Chan
mesh_terms: D003661:Decision Support Techniques; D004867:Equipment Design / Q000592:standards*; D005069:Evaluation Studies as Topic; D017143:Fuzzy Logic; D006801:Humans; D008962:Models, Theoretical; D011795:Surveys and Questionnaires / Q000592:standards
keywords: Usability; analytic hierarchy process (AHP); fuzzy comprehensive evaluation