An approach to construct entropy and similarity measure for interval-valued intuitionistic fuzzy sets

This paper improves the definition of entropy for interval-valued intuitionistic fuzzy sets(IVIFSs) and gives a new method to construct it. Comparing with previous definitions of entropy, this definition is more intuitive and the proof is given at the same time. The paper also studies the relation between entropy and similarity measure for interval-valued Intuitionistic fuzzy sets(IVIFSs) and gives an approach to construct similarity measure using the new entropy formula. At last, these proposed formulas are illustrated and verified by a numerical example.