Multiple Criteria Decision Making Methods Based On Hesitant Fuzzy Linguistic Term Sets

Hesitant fuzzy linguistic term sets ( HFLTS ) are new extension of fuzzy linguistic. Compared with the traditional fuzzy linguistic methods which use a single linguistic term to describe the linguistic variable, the value of HFLTS is an ordered and coherent subset of the linguistic term set. This allows experts to adopt a more flexible linguistic to express their assessment and ideas, and enhances the feasibility,flexibility and credibility of decision-making information expression.This paper studies the possibility degree comparison formula of hesitant fuzzy linguistic term sets and analyzes problems of the existing possibility degree formulas.Three kinds of possibility degree formulas are proposed based on presenting possibility degree axiom. The five mutual equivalent formulas of the first kind is based on the idea of interval comparison method. Another five mutual equivalent formulas are proposed on basing of the first kind of formulas, and the third kind of possibility degree formulas with respect to HFLTSs is proposed by probability criterion of uniform distribution.The hesitance degree and distance measure of hesitant fuzzy linguistic term sets are studied. Hesitant fuzzy linguistic reflects the hesitation degree of the decision maker of the evaluation results, but the existing distance measure only considering the size of the terms, and does not take into account the number of terms. In order to reasonably express distance measure between hesitant fuzzy linguistic terms sets, this paper proposes the concept of hesitant fuzzy linguistic hesitance degree, combined with the existing distance measure to put forward a new more reasonable distance formula, reducing the loss of information in the decision-making process.Hesitant fuzzy linguistic multiple criteria decision making methods are studied.For the multiple criteria decision making problem which criteria weights are known,the methods based on the possibility degree are proposed; based on the distance measure, the hesitant fuzzy linguistic TOPSIS method is proposed to solve multiple criteria decision making problem which criteria weights are unknown, and compared by an example and a number of other methods show that these methods are effective and reasonable.