“…Through years of development of fuzzy logic, many researchers have been developing methods of comparing sets and fuzzy numbers. Among them, it is impossible not to recall that several fuzzy number comparison methods and indices have been researched since 1977 by Zadeh [12], Yager [10,11], Kaufman [14,15], Chang [5], and Amado [1]. Bortolan and Degani [5] and Dadgostar [1] reviewed some of the methods for ranking fuzzy sets, including Yager's first, second, and third indexes, Chang's algorithm, Adamo's method, Baas and Kwakernaak's method [2], Baldwin and Guild's method [3], Kerre's method [9], Jain's method [7,8], and Dubois and Prade's four grades [6] of dominance (PD, PSD, ND, NSD).…”