Cognitive effort reduction within group decision making through aggregation and disaggregation of individual preferences

Most of multicriteria methods require the specification of different preference parameters. This necessitates a considerable cognitive effort from the decision maker, especially for those with no or limited knowledge about multicriteria analysis. The situation is further complicated within a group of decision makers. In this paper, we propose a multicriteria classification approach that relies on an aggregation/disaggregation strategy within a group of decision makers, permitting thus to considerably reduce the needed cognitive effort at individual as well as group levels. The aggregation/disaggregation strategy is known for its ability to reduce the cognitive effort at the level of individual decision makers. At group level, a simple majority rule is used to generate consensual decisions with no additional information from the decision makers. A didactic example is used to illustrate the proposed approach.