International Journal of Advanced Research in Computer Science and Software Engineering (IJARCSSE)
Similarity measure for fuzzy sets is one of the researched topics of fuzzy set theory. The literature is vast and growing. This paper is to revisit the definitions of similarity measure which are predominant in the literature of fuzzy set theory. The authors wish to analyze these existing definitions with the extended definition of complementation of fuzzy sets on the basis of reference function. This paper summarizes some of the developments in this research area of fuzzy set theory.