VIKOR method using interval type two fuzzy sets

One of the frequently used multi-attribute decision making (MADM) methods is VIKOR, which provides a compromise solution with maximum group utility and minimum regret of decision makers with non-commensurable and conflicting attributes. In the literature, VIKOR method has been extended to the fuzzy case using type-1 fuzzy sets. Type-2 fuzzy sets let the fuzzy membership functions to be defined for providing us more design degrees of freedom and flexibility. In this paper, we developed an interval type-2 fuzzy VIKOR method including a fuzzy ranking method for interval type-2 fuzzy sets. Interval type-2 fuzzy weights for decision makers' strategies have also been used in the proposed method. A sensitivity analysis has been applied to see the behavior of our decision with respect to the changing weights of maximum group utility strategies. We showed the applicability of the proposed method through an existent problem in the literature.