A general theorem and eight corollaries in search of correct decision

Abstract

The main theorem established in this study and its corollaries summarize and generalize the existing results on optimal aggregation of experts judgments under uncertain pairwise choice situations. In particular, we explicate the link between the optimal decision procedure and the decision maker's preferences and biases and the judgmental competences of his consultants. The general theorem directly clarifies under what circumstances the optimal decision rule should be the democratic simple majority rule, the elitist expert rule, an intermediate weighted simple majority rule or a biased weighted or simple qualified majority rule.