Dictatorial voting operators

Voting operators map n-tuples of subsets of a given set X of candidates (the voters choices) into subsets of X (the social choice). This paper characterizes dictatorial voting operators by means of three conditions (the non-emptiness condition A1, the independence condition A2 and the resoluteness condition A3) motivated by the idea of transferring to the social choice properties common to all the voters choices. The result is used to refine Lahiris (2001) characterization and to derive dictatorial results in other three types of aggregation problems, in which choice functions are transformed into choice functions, binary relations into choices and binary relations into binary relations.Received: 20 May 2002, Accepted: 5 August 2003, JEL Classification: D70, D71Antonio Quesada: Present address: Departament dEconomia, Facultat de Ciéncies Económiques i Empresarials, Universitat Rovira i Virgili, Avinguda de la Universitat 1, 43204 Reus (Tarragona), Spain. I would like to express my gratitude to the referees for their contribution to improve this paper.Part of this work was done at the Departament dAnálisi Económica, Facultat dEconomia, Universitat de Valéncia, Avinguda dels Tarongers s/n, 46022 Valéncia, Spain.