An outranking sorting method for multi-criteria group decision making using intuitionistic fuzzy sets

In real world multi-criteria group decision making (MCGDM) problems, the decision making information provided by the decision makers is often imprecise or uncertain because of a lack of data, time pressure, or the decision makers’ limited information-processing capabilities. Intuitionistic fuzzy sets, however, have been shown to have greater imprecision and an increased ambiguity than ordinary fuzzy sets. For these reasons, this paper proposes a new outranking sorting method for group decision making using intuitionistic fuzzy sets. Based on a proposed intuitionistic fuzzy support function, risk function and credibility function, we first propose a new method for the construction of an intuitionistic fuzzy outranking relation to exploit the sorting problems. Then we extend the proposed intuitionistic fuzzy sorting method to take account of group decision techniques and to develop an adaptive search and adjustment approach for the group consensus. Finally, a numerical example for a bridge risk assessment is provided to elucidate the details of the proposed method, and then this method is compared with other current methods to further demonstrate its flexibility.