Hesitant Fuzzy Linguistic Term Sets for Decision Making

TLDR

Dealing with uncertainty is challenging, and while hesitant fuzzy sets have been used for quantitative settings, similar situations arise in qualitative contexts where experts consider multiple linguistic terms. The paper introduces hesitant fuzzy linguistic term sets to enrich linguistic elicitation in decision making. The authors present a multicriteria decision‑making model that uses context‑free grammars and comparative terms to represent experts’ linguistic expressions as hesitant fuzzy linguistic term sets.

Abstract

Dealing with uncertainty is always a challenging problem, and different tools have been proposed to deal with it. Recently, a new model that is based on hesitant fuzzy sets has been presented to manage situations in which experts hesitate between several values to assess an indicator, alternative, variable, etc. Hesitant fuzzy sets suit the modeling of quantitative settings; however, similar situations may occur in qualitative settings so that experts think of several possible linguistic values or richer expressions than a single term for an indicator, alternative, variable, etc. In this paper, the concept of a hesitant fuzzy linguistic term set is introduced to provide a linguistic and computational basis to increase the richness of linguistic elicitation based on the fuzzy linguistic approach and the use of context-free grammars by using comparative terms. Then, a multicriteria linguistic decision-making model is presented in which experts provide their assessments by eliciting linguistic expressions. This decision model manages such linguistic expressions by means of its representation using hesitant fuzzy linguistic term sets.