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arXiv · 2111.14417

An axiomatic derivation of Condorcet-consistent social decision rules

Aurelien Mekuko Yonta·Matias Núñez·Issofa Moyouwou·Nicolas Gabriel Andjiga
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Abstract

A social decision rule (SDR) is any non-empty set-valued map that associates any profile of individual preferences with the set of (winning) alternatives. An SDR is Condorcet-consistent if it selects the set of Condorcet winners whenever this later is non-empty. We propose a characterization of Condorcet consistent SDRs with a set of minimal axioms. It appears that all these rules satisfy a weaker Condorcet principle - the top consistency - which is not explicitly based on majority comparisons while all scoring rules fail to meet it. We also propose an alternative characterization of this class of rules using Maskin monotonicity.

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Aurelien Mekuko Yonta, Matias Núñez, Issofa Moyouwou, Nicolas Gabriel Andjiga. 2021-11-29. An axiomatic derivation of Condorcet-consistent social decision rules. https://arxiv.org/abs/2111.14417

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