Construction of a two-parameters fuzzy outranking relation from fuzzy evaluations

At the early stages of design process, several design concepts are proposed as potential solutions. The selection of the most appropriate one is based on their evaluation with respect to several conflicting criteria. In this paper, we consider the case where the evaluations of design concepts with respect to different criteria are represented by means of fuzzy numbers. We deal with the construction of a two parameters fuzzy outranking relation from fuzzy evaluations. It is based on the aggregation of outranking indices associated with alpha-cuts. This fuzzy outranking index allows the decision maker to adopt different strategies by choosing a degree of optimism and a degree of aggressiveness.