Modelling experts’ attitudes in group decision making

Nowadays, important decisions that have a significant impact either in societies or in organizations are commonly made by a group rather than a single decision maker, which might require more than a majority rule to obtain a real acceptance. Consensus-reaching processes provide a way to drive group decisions which are more accepted and appreciated by people affected by such a decision. These processes care about different consensus measures to determine the agreement in the group. The correct choice of a consensus measure that reflects the attitude of decision makers is a key issue for improving and optimizing consensus-reaching processes, which still requires further research. This paper studies the concept of group’s attitude towards consensus, and presents a consensus model that integrates it in the measurement of consensus, through an extension of OWA aggregation operators, the so-called Attitude-OWA. The approach is applied to the solution of a real-like group decision making problem with the definition of different attitudes, and the results are analysed.