The Core of the Participatory Budgeting Problem

  • Brandon FainEmail author
  • Ashish Goel
  • Kamesh Munagala
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10123)


In participatory budgeting, communities collectively decide on the allocation of public tax dollars for local public projects. In this work, we consider the question of fairly aggregating preferences to determine an allocation of funds to projects. We argue that the classic game theoretic notion of core captures fairness in the setting. To compute the core, we first develop a novel characterization of a public goods market equilibrium called the Lindahl equilibrium. We then provide the first polynomial time algorithm for computing such an equilibrium for a broad set of utility functions. We empirically show that the core can be efficiently computed for utility functions that naturally model data from real participatory budgeting instances, and examine the relation of the core with the welfare objective. Finally, we address concerns of incentives and mechanism design by developing a randomized approximately dominant-strategy truthful mechanism building on the Exponential Mechanism from differential privacy.


Utility Function Proportional Fairness Approval Vote Fair Allocation Core Allocation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank Anilesh Krishnaswamy for useful discussions, and the Stanford Crowdsourced Democracy Team for the use of their data.


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Copyright information

© Springer-Verlag GmbH Germany 2016

Authors and Affiliations

  1. 1.Department of Computer ScienceDuke UniversityDurhamUSA
  2. 2.Management Science and Engineering DepartmentStanford UniversityStanfordUSA

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