The role of fuzzy sets in decision sciences: Old techniques and new directions

We try to provide a tentative assessment of the role of fuzzy sets in decision analysis. We discuss membership functions, aggregation operations, linguistic variables, fuzzy intervals and the valued preference relations they induce. The importance of the notion of bipolarity and the potential of qualitative evaluation methods are also pointed out. We take a critical standpoint on the state-of-the-art, in order to highlight the actual achievements and question what is often considered debatable by decision scientists observing the fuzzy decision analysis literature.

► A critical discussion of fuzzy sets in decision analysis.
► A comparison between the use of quantitative and qualitative scales in decision evaluation.
► A review of fuzzy weighted averages and fuzzy extensions of the AHP method of Saaty.
► The outline of a new approach to the definition and the classification of fuzzy interval ranking techniques.