Budget aggregation deals with the social choice problem of distributing an exogenously given budget among a set of public projects, given agents' preferences. Taking a game-theoretic perspective, we study budget-aggregation games where each agent has virtual decision power over some fraction of the budget. We investigate the structure and show efficient computability of Nash equilibria for various common preference models in this setting. In particular, we show that equilibria for Leontief utilities can be found in polynomial time, solving an open problem from Brandt et al. [2023], and give an explicit polynomial-time algorithm for computing equilibria for $\ell_1$ preferences.

翻译：预算聚合处理的是在给定代理人偏好的情况下，将外生给定的预算分配给一组公共项目的社会选择问题。本文从博弈论视角出发，研究预算聚合博弈，其中每个代理人对预算的某个比例拥有虚拟决策权。我们探讨了该设定下多种常见偏好模型的均衡结构，并证明了纳什均衡的高效可计算性。特别地，我们证明了列昂惕夫效用下的均衡可在多项式时间内求解，从而解决了Brandt等人[2023]提出的一个公开问题，并给出了计算ℓ₁偏好下均衡的显式多项式时间算法。