Multiple attribute group decision making in interval type-2 fuzzy environment using a new distance formulation

Type‐2 fuzzy sets are generalisations of ordinary fuzzy sets in which the membership grades are characterised by fuzzy membership functions. Here, we consider the problem of finding the distance between two interval type‐2 fuzzy sets (IT2‐FSs). We define the formulation of calculating the distance between two IT2‐FSs based on a new definition of centroid for an IT2‐FS and explain an algorithm for obtaining it. Then, based on our proposed distance formulation, we present a method to deal with fuzzy multiple attributes group decision‐making (FMAGDM) problems. We also use two examples to illustrate the FMAGDM process of the proposed method. The method provides us with a useful way to deal with FMAGDM problems based on IT2‐FSs.