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arXiv · 2504.14195

The River Method

Michelle Döring·Markus Brill·Jobst Heitzig
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Abstract

We introduce River, a novel Condorcet-consistent voting method that is based on pairwise majority margins and can be seen as a simplified variation of Tideman's Ranked Pairs method. River is simple to explain, simple to compute even 'by hand', and gives rise to an easy-to-interpret certificate in the form of a directed tree. Like Ranked Pairs and Schulze's Beat Path method, River is a refinement of the Split Cycle method and shares with those many desirable properties, including independence of clones. Unlike the other three methods, River satisfies a strong form of resistance to agenda-manipulation that is known as independence of Pareto-dominated alternatives.

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Michelle Döring, Markus Brill, Jobst Heitzig. 2025-04-19. The River Method. https://arxiv.org/abs/2504.14195

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