Discussion on Definitions for Similarity Measures of Intuitionistic Fuzzy Sets

AbstractIn pattern recognition field based on intuitionistic fuzzy sets, a lot of papers have cited Xu (2007) in their references. However, when examining Xu (2007), we found that the definition of similarity measures in the paper was contradictive. In the paper we will show that the four similarity measures proposed by Xu (2007) are inconsistent with his definition of similarity measure. We suggest using the definition of Mitchell (2003) for similarity measures to rectify this problem.