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arXiv · 2411.18790

Fast Schulze Voting Using Quickselect

Arushi Arora·David Eppstein·Randy Le Huynh
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Abstract

The Schulze voting method aggregates voter preference data using maxmin-weight graph paths, achieving the Condorcet property that a candidate who would win every head-to-head contest will also win the overall election. Once the voter preferences among $m$ candidates have been arranged into an $m\times m$ matrix of pairwise election outcomes, a previous algorithm of Sornat, Vassilevska Williams and Xu (EC '21) determines the Schulze winner in randomized expected time $O(m^2\log^4 m)$. We improve this to randomized expected time $O(m^2\log m)$ using a modified version of quickselect.

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Arushi Arora, David Eppstein, Randy Le Huynh. 2024-11-27. Fast Schulze Voting Using Quickselect. https://doi.org/10.7155/jgaa.v30i1.3030

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