The q-majority efficiency of positional rules

Sébastien Courtin (1) , Mathieu Martin (1) , Issofa Moyouwou (2)

1 THEMA - Théorie économique, modélisation et applications
2 École normale supérieure [ENS] - Yaoundé 1

According to a given quota q, a candidate a is beaten by another candidate b if at least a proportion of q individuals prefer b to a. The q-Condorcet efficiency of a voting rule is the probability that the rule selects a q-Condorcet winner (q-CW), that is any candidate who is never beaten under the q-majority. Closed form representations are obtained for the q-Condorcet efficiency of positional rules (simple and sequential) in three-candidate elections. This efficiency is significantly greater for sequential rules than for simple positional rules.

Mots clés: Positional rules (simple and sequential); Majority efficiency; q -Majority

Domaines: Economies et finances

Sébastien Courtin, Mathieu Martin, Issofa Moyouwou. The q-majority efficiency of positional rules. Theory and Decision, 2015, 79 (1), pp.31 - 49. ⟨10.1007/s11238-014-9451-2⟩. ⟨hal-00914907⟩