Strategic Cost Selection in Participatory Budgeting

Piotr Faliszewski, Łukasz Janeczko, Andrzej Kaczmarczyk, Grzegorz Lisowski, Piotr Skowron, Stanisław Szufa, Mateusz Szwagierczak

Keywords: Participatory Budgeting, Social Choice, Game Theory, Equilibria

Abstract:

We study strategic behavior of project proposers in the context of approval-based
participatory budgeting (PB). In our model we assume that the votes are fixed and
known and the proposers want to set as high project prices as possible, provided
that their projects get selected and the prices are not below the minimum costs of
their delivery. We study the existence of pure Nash equilibria (NE) in such games,
focusing on the AV/Cost, Phragmen, and Method of Equal Shares rules. We also
provide an experimental study of cost selection on real-life PB election data.

Primary Area: Theory (e.g., control theory, learning theory, algorithmic game theory)

Submission Number: 12502