A complex method based on TOPSIS and Choquet integral to solve multi attribute group decision making problems with interval type-2 fuzzy numbers

TOPSIS method is a most useful tool for solving MADM problems, also, Choquet integral method is another powerful method which, is able to manage interaction criteria. In this paper, we combine both methods to use from their benefits. First, we will introduce a new method for computing the distance between IT2FSs. Then, we proposed a hybrid method based on TOPSIS and Choquet integral in fuzzy type-2 environment. Numerical examples are considered to illustrate the proposed methods.