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arXiv · 2112.10407

Axiomatic characterizations of consistent approval-based committee choice rules

Martin Lackner·Piotr Skowron
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Abstract

We prove axiomatic characterizations of several important multiwinner rules within the class of approval-based committee choice rules. These are voting rules that return a set of (fixed-size) committees. In particular, we provide axiomatic characterizations of Proportional Approval Voting, the Chamberlin--Courant rule, and other Thiele methods. These rules share the important property that they satisfy an axiom called consistency, which is crucial in our characterizations.

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Martin Lackner, Piotr Skowron. 2021-12-20. Axiomatic characterizations of consistent approval-based committee choice rules. https://arxiv.org/abs/2112.10407

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