30 March – Dominic Peters* “Proportional Participatory Budgeting with Additive Utilities” (Hosted by Marcus Pivato)
* Harvard University
1PM GMT: 10AM Montevideo, 8AM Boston, 2PM Paris, 4PM in Moscow, 10PM in Seoul, and 2AM (next day) in Auckland.
Abstract. We study voting rules for participatory budgeting, where a group of voters collectively decides which projects should be funded using a common budget. We allow the projects to have arbitrary costs, and the voters to have arbitrary additive valuations over the projects. We formulate two axioms that guarantee proportional representation to groups of voters with common interests. To the best of our knowledge, all known rules for participatory budgeting do not satisfy either of the two axioms; in addition we show that the most prominent proportional rules for committee elections (such as Proportional Approval Voting) cannot be adapted to arbitrary costs nor to additive valuations so that they would satisfy our axioms of proportionality. We construct a simple and attractive voting rule that satisfies one of our axioms (for arbitrary costs and arbitrary additive valuations), and that can be evaluated in polynomial time. We prove that our other stronger axiom is also satisfiable, though by a computationally more expensive and less natural voting rule.
Joint work with Grzegorz Pierczyński and Piotr Skowron (https://arxiv.org/abs/2008.13276).
The talks are also announced and the slides/recordings posted on the seminar website https://sites.google.com/view/2021onlinescwseminars/home.
Here is the Zoom link information:
Meeting ID: 926 6298 7426