It is commonly accepted that the multiplicity of equilibria is ubiquitous in preference aggregation games with any voting method. We prove that this mul- tiplicity is greatly reduced under some mild restrictions over social preferences when each voter can vote for as many candidates as she...

This work provides necessary and sufficient conditions for the dominance solvability of approval voting games. Our conditions are very simple since they are based on the approval relation, a binary relation between the alternatives. We distinguish between two sorts of dominance solvability and...

Dans ce papier, de nouveaux résultats sont fournis dans le modèle de Poisson-Myerson. Ces résultats se révèlent utiles pour l'étude du vote par assentiment. En effet, le Théorème d'Equivalence des Magnitudes (MET) réduit fortement la complexité du calcul des magnitudes des pivots. Un...

Approval voting features are analysed in a context of large elections with strategic voters: Myerson's Large Poisson Games. I first establish the Magnitude Equiva- lence Theorem (MET) which substantially reduces the complexity of computing the magnitudes of pivotal events. I also show that the...

Empiriquement, on observe que la majorité des Etats a fait le choix d'un système d'imposition progressif. Pourtant, le fondement théorique de ce choix n'est pas évident. Si l'on interprète le système d'imposition appliquée comme le résultat d'un jeu entre deux partis politiques...

This paper provides a theoretical foundation which supports the degressive proportionality principle in apportionment problems. The core of the argument is that each individual derives utility from the fact that the collective decision matches her own will with some frequency, with marginal...

A l'occasion du premier tour des élections présidentielles du 22 avril 2012, les électeurs de trois communes françaises ont été invités à tester in situ le vote par approbation ainsi que trois versions du vote par évaluation. Ce papier a pour objet de présenter les résultats de cette...

Under evaluative voting, the voter freely grades each candidate on a numerical scale, with the winning candidate being determined by the sum of the grades they receive. This paper compares evaluative voting with the two-round system, reporting on an experiment which used various evaluation...

This Note contains the recommendation for a mathematical basis for the apportionment of the seats in the European Parliament between the Member States of the European Union. This is the unanimous recommendation of the Participants in the Cambridge Apportionment Meeting, held at the instigation...

The paper studies a specific reinforcement learning rule in two-player games when each player faces a unidimensional strategy set. The essential feature of the rule is that a player keeps on incrementing her strategy in the same direction if and only if her utility increases. The paper...