Epistemic Selection of Costly Alternatives: The Case of Participatory Budgeting

Simon Rey; Ulle Endriss

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arXiv · 2304.10940

Epistemic Selection of Costly Alternatives: The Case of Participatory Budgeting

Simon Rey·Ulle Endriss

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Abstract

We initiate the study of voting rules for participatory budgeting using the so-called epistemic approach, where one interprets votes as noisy reflections of some ground truth regarding the objectively best set of projects to fund. Using this approach, we first show that both the most studied rules in the literature and the most widely used rule in practice cannot be justified on epistemic grounds: they cannot be interpreted as maximum likelihood estimators, whatever assumptions we make about the accuracy of voters. Focusing then on welfare-maximising rules, we obtain both positive and negative results regarding epistemic guarantees.

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BibTeX RIS

Simon Rey, Ulle Endriss. 2023-04-21. Epistemic Selection of Costly Alternatives: The Case of Participatory Budgeting. https://arxiv.org/abs/2304.10940

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