Multiagent Decision Making, Fuzzy Prevision, and Consensus

Some multi-objective and multi-person decision making models are introduced. Objectives and alternatives are considered as elements of two algebras of events, and weights and scores are assumed to be values of crisp or fuzzy measures. Then the problem of verifying coherence is considered and the aggregation of scores is performed with respect to a suitable t-conorm. Moreover decision makers are identified with points of a metric space, and consensus in a group is obtained if the pairwise distances of the elements of the group do not exceed a fixed threshold. Procedures for enhancing, or achieving consensus are considered. Finally, further multi-objective and multi-person decision making models are introduced based on the concept of prevision. Precisely objectives and alternatives are assumed to be random numbers and weights and scores crisp or fuzzy previsions.