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arXiv · 1508.03538

Welfare Maximization Entices Participation

Florian Brandl·Felix Brandt·Johannes Hofbauer
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Abstract

We consider randomized mechanisms with optional participation. Preferences over lotteries are modeled using skew-symmetric bilinear (SSB) utility functions, a generalization of classic von Neumann-Morgenstern utility functions. We show that every welfare-maximizing mechanism entices participation and that the converse holds under additional assumptions. Two important corollaries of our results are characterizations of an attractive randomized voting rule that satisfies Condorcet-consistency and entices participation. This stands in contrast to a well-known result by Moulin (1988), who proves that no deterministic voting rule can satisfy both properties simultaneously.

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Florian Brandl, Felix Brandt, Johannes Hofbauer. 2015-08-14. Welfare Maximization Entices Participation. https://arxiv.org/abs/1508.03538

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