The group analytic hierarchy process (G-AHP) with preference aggregation by type-2 fuzzy envelope of extended hesitant fuzzy linguistic term set (EHFLTS)

Solving practical selection problems frequently involves analyzing imprecise and uncertain input. In the absence of unequivocal measures for ranking options, the decision maker needs to resort to pairwise comparisons and capture preferences using comparative linguistic expressions. If multiple decision-makers are involved, the complexity of analysis grows and consistency of results may become questionable. This paper proposes a group decision-making method that draws from the fuzzy Analytic Hierarchy Process (FAHP) and utilizes the type-2 fuzzy envelope of an extended hesitant fuzzy linguistic term set (EHFLTS) to aggregate the preferences of multiple decision-makers. This approach avoids the need for normalization or transformation of the input, thereby reducing information loss. The method’s performance is demonstrated using a notional example of a contractor selection problem. The result (the final ranking of options) is then compared with results generated by means of methods presented in the literature. The proposed approach is a flexible and effective group decision support method that addresses key gaps observed in the existing methods.