Multicriteria linguistic decision making based on hesitant fuzzy linguistic term sets and the aggregation of fuzzy sets

In this paper, we present a new method for multicriteria linguistic decision making based on hesitant fuzzy linguistic term sets using the pessimistic attitude and the optimistic attitude of the decision-maker. The proposed method aggregates the fuzzy sets in each hesitant fuzzy linguistic term set into a fuzzy set and performs the αα-cut operations to these aggregated fuzzy sets to get intervals, respectively, where α∈(0,1]α∈(0,1]. For each alternative, it performs the minimum operations and the maximum operations among the obtained intervals to get the derived intervals, respectively, where the minimum operation and the maximum operation among intervals denote the pessimistic attitude and the optimistic attitude of the decision-maker, respectively. Then, for each alternative, it uses the likelihood method for ranking the priority between the obtained intervals to get the preference order of the alternatives for the decision-maker with the pessimistic attitude and the optimistic attitude, respectively. The proposed method is more flexible than the existing methods for multicriteria linguistic decision making due to the fact that it considers the pessimistic attitude and the optimistic attitude of the decision-maker.