Ranking L–R fuzzy number based on deviation degree

This paper proposed a novel approach to ranking fuzzy numbers based on the left and right deviation degree (L–R deviation degree). In the approach, the maximal and minimal reference sets are defined to measure L–R deviation degree of fuzzy number, and then the transfer coefficient is defined to measure the relative variation of L–R deviation degree of fuzzy number. Furthermore, the ranking index value is obtained based on the L–R deviation degree and relative variation of fuzzy numbers. Additionally, to compare the proposed approach with the existing approaches, five numerical examples are used. The comparative results illustrate that the approach proposed in this paper is simpler and better.