Collective decision making under possibilistic uncertainty. Principles and characterization

Nahla Ben Amor (1) , Fatma Essghaier (1, 2) , Hélène Fargier (2, 3)

1 LARODEC - Laboratoire de Recherche Opérationnelle de Décision et de Contrôle de Processus
2 IRIT-ADRIA - Argumentation, Décision, Raisonnement, Incertitude et Apprentissage
3 CNRS - Centre National de la Recherche Scientifique

This paper raises the question of collective decision making under possibilistic uncertainty. We study several egalitarian decision rules and show that in the context of a possibilistic representation of uncertainty, the use of an egalitarian collective utility function allows us to get rid of the Timing Effect. Making a step further, we prove that if both the agents’ preferences and the collective ranking of the decisions satisfy Dubois and Prade’s axioms (Dubois, Prade, 1995), and particularly risk aversion, and Pareto unanimity, then the egalitarian collective aggregation is compulsory. This result can be seen as an ordinal counterpart of Harsanyi’s theorem (Harsanyi, 1955). The picture is then completed by the proposition and the characterization of an optimistic counterpart of this pessimistic decision rule.

Mots clés: Loteries possibilistes; Décision sous incertitude; Choix collectif; Axiomatisation; decision Making under uncertainty; possibilistic lotteries; collective Choice; axiomatization; timing effect

Domaines: Intelligence artificielle [cs.AI]; Apprentissage [cs.LG]; Logique en informatique [cs.LO]; Informatique et langage [cs.CL]

Nahla Ben Amor, Fatma Essghaier, Hélène Fargier. Collective decision making under possibilistic uncertainty. Principles and characterization. Revue des Sciences et Technologies de l'Information - Série RIA : Revue d'Intelligence Artificielle, 2015, 29 (5), pp.515-542. ⟨10.3166/RIA.29.515-542⟩. ⟨hal-01531177⟩