# Multi-winner scoring election methods: Condorcet consistency and paradoxes

@article{Diss2016MultiwinnerSE, title={Multi-winner scoring election methods: Condorcet consistency and paradoxes}, author={Mostapha Diss and Ahmed Doghmi}, journal={Public Choice}, year={2016}, volume={169}, pages={97-116} }

The goal of this paper is to propose a comparison of four multi-winner voting rules, k-Plurality, k-Negative Plurality, k-Borda, and Bloc. These four election methods are extensions of usual scoring rules designed for electing a single winner and are compared on the basis of two criteria. The first comparison is based on the Condorcet committee efficiency which is defined as the conditional probability for a peculiar voting rule to select the Condorcet committee, provided that such a committee…

## 20 Citations

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A comparison of five multi-winner voting rules widely studied in the literature of social choice theory by taking into account a probabilistic approach using the well-known Impartial Anonymous Culture (IAC) assumption tells us that the k-Borda rule has the highest performance amongst all the considered voting rules.

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This paper considers committee selection rules that can be viewed as generalizations of single-winner scoring rules, including SNTV, Bloc, k-Borda, STV, as well as several variants of the Chamberlin–Courant rule and the Monroe rule and their approximations.

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It turns to be that, in general, Condorcet committees are significantly exposed to social unacceptability.

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