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arXiv · 1807.03979

Paradoxes in Sequential Voting

Oren Dean·Yakov Babichenko·Moshe Tennenholtz
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Abstract

We analyse strategic, complete information, sequential voting with ordinal preferences over the alternatives. We consider several voting mechanisms: plurality voting and approval voting with deterministic or uniform tie-breaking rules. We show that strategic voting in these voting procedures may lead to a very undesirable outcome: Condorcet winning alternative might be rejected, Condorcet losing alternative might be elected, and Pareto dominated alternative might be elected. These undesirable phenomena occur already with four alternatives and a small number of voters. For the case of three alternatives we present positive and negative results.

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Oren Dean, Yakov Babichenko, Moshe Tennenholtz. 2018-07-11. Paradoxes in Sequential Voting. https://arxiv.org/abs/1807.03979

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