Interval type-2 hesitant fuzzy set and its application in multi-criteria decision making

•The interval type-2 hesitant fuzzy set (IT2HFS) is defined.•Score function, operations and aggregation operators of IT2HFS are proposed.•MCDM method based on IT2HFS is suggested.

This paper proposes the concept of interval type-2 hesitant fuzzy set (IT2HFS), which is a generalization of interval type-2 fuzzy set and hesitant fuzzy set. Firstly, IT2HFS is defined, and its operation laws and corresponding properties are discussed. Then, its score function and aggregation operators are also outlined. Moreover, a multi-criteria decision making method for interval type-2 hesitant fuzzy problems is suggested based on the aggregation operators and score function. Finally, an example is illustrated to demonstrate the validity and feasibility of the proposed method.