A Consensus Model for Group Decision Making with Hesitant Fuzzy Linguistic Information

Group Decision Making (GDM) is a usual process in companies and administration in which complex decision problems are solved taking into account different points of view from different experts involved in the decision situation. Notwithstanding, in principle group decisions should be better accepted than decisions made by a single decision maker because they try to include several viewpoints, sometimes the decision processes do not consider the agreement in the solution, therefore such solutions can fail in their goal. To overcome such a problem, a consensus reaching process is added to GDM processes to obtain solutions with a high degree of agreement. The complexity of GDM problems are often due to the uncertainty related to the imprecision and vagueness of the meaning of the decision situation that is modelled by linguistic descriptors. Different linguistic consensus models have successfully dealt with these GDM problems. However, recently it has been pointed out that in GDM problems dealing with linguistic information may be necessary to offer a higher flexibility to experts for eliciting their preferences to manage mainly their hesitancy about linguistic assessments when a single linguistic term does not adjust enough to their knowledge/preference. This contribution provides a novel consensus model for GDM problems dealing with Hesitant Fuzzy Linguistic Term Sets (HFLTS) that have been proposed to deal with hesitancy in linguistic GDM problems.