Consensus Measures and Adjusting Inconsistency of Linguistic Preference Relations in Group Decision Making

This paper presents a method for consensus measures and adjusting inconsistency of linguistic preference relations in group decision-making (GDM). Several consensus measures are defined by comparing positions of alternatives between individual ordered vectors and a collective ordered vector. In such a way, the consensus situation is evaluated in each moment in a more realistic way. Feedback mechanism would be applied if the consensus degree of all experts does not reach the required consensus level. This feedback mechanism is simple and easy computing process to help experts change their opinions in order to obtain the consensus level. It is based on the use of individual linguistic preferences, collective and individual ordered vectors of alternatives. It is also based on the use of fuzzy majority of consensus, represented by means of a linguistic quantifier.