Abstract
We study the setting of committee elections, where a group of individuals needs to collectively select a given-size subset of available objects. This model is relevant for a number of real-life scenarios including political elections, participatory budgeting, and facility-location. We focus on the core—the classic notion of proportionality, stability and fairness. We show that for a number of restricted domains including voter-interval, candidate-interval, single-peaked, and single-crossing preferences the core is non-empty and can be found in polynomial time. We show that the core might be empty for strict top-monotonic preferences, yet we introduce a relaxation of this class, which guarantees non-emptiness of the core. Our algorithms work both in the randomized and discrete models. We also show that the classic known proportional rules do not return committees from the core even for the most restrictive domains among those we consider (in particular for 1D-Euclidean preferences). We additionally prove a number of structural results that give better insights into the nature of some of the restricted domains, and which in particular give a better intuitive understanding of the class of top-monotonic preferences.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
Typically a voting rule would return a single winning committee, but ties are possible.
References
Aziz, H., Bogomolnaia, A., Moulin, H.: Fair mixing: the case of dichotomous preferences. In: EC-2019, pp. 753–781 (2019)
Aziz, H., Brill, M., Conitzer, V., Elkind, E., Freeman, R., Walsh, T.: Justified representation in approval-based committee voting. Soc. Choice Welfare 48(2), 461–485 (2017). https://doi.org/10.1007/s00355-016-1019-3
Aziz, H., Elkind, E., Faliszewski, P., Lackner, M., Skowron, P.: The Condorcet principle for multiwinner elections: from shortlisting to proportionality. In: IJCAI-2017, pp. 84–90, August 2017
Aziz, H., Lee, B.: The expanding approvals rule: improving proportional representation and monotonicity. Soc. Choice Welfare 54(1), 1–45 (2020). https://doi.org/10.1007/s00355-019-01208-3
Barberà, S., Moreno, B.: Top monotonicity: a common root for single peakedness, single crossing and the median voter result. Games Econom. Behav. 73(2), 345–359 (2011)
Black, D.: On the rationale of group decision-making. J. Polit. Econ. 56(1), 23–34 (1948)
Brandt, F.: Rolling the dice: recent results in probabilistic social choice. In: Endriss, U. (ed.) Trends in Computational Social Choice, pp. 3–26. AI Access (2017)
Brill, M., Gölz, P., Peters, D., Schmidt-Kraepelin, U., Wilker, K.: Approval-based apportionment. In: AAAI-2020, pp. 1854–1861 (2020)
Burdges, J., et al.: Overview of Polkadot and its design considerations. arXiv preprint arXiv:2005.13456 (2020)
Cevallos, A., Stewart, A.: A verifiably secure and proportional committee election rule. arXiv preprint arXiv:2004.12990 (2020)
Chalkiadakis, G., Elkind, E., Wooldridge, M.: Computational aspects of cooperative game theory. In: Synthesis Lectures on Artificial Intelligence and Machine Learning, vol. 5, no. 6, pp. 1–168 (2011)
Cheng, Y., Jiang, Z., Munagala, K., Wang, K.: Group fairness in committee selection. In: EC-2019, pp. 263–279 (2019)
Dummett, M.: Voting Procedures. Oxford University Press, Oxford (1984)
Elkind, E., Faliszewski, P., Skowron, P.: A characterization of the single-peaked single-crossing domain. Soc. Choice Welfare 54, 167–181 (2020). https://doi.org/10.1007/s00355-019-01216-3
Elkind, E., Faliszewski, P., Skowron, P., Slinko, A.: Properties of multiwinner voting rules. Soc. Choice Welfare 48(3), 599–632 (2017). https://doi.org/10.1007/s00355-017-1026-z
Elkind, E., Lackner, M.: Structure in dichotomous preferences. In: IJCAI-2015, pp. 2019–2025 (2015)
Elkind, E., Lackner, M., Peters, D.: Structured preferences. In: Trends in Computational Social Choice, pp. 187–207 (2017)
Fain, B., Goel, A., Munagala, K.: The core of the participatory budgeting problem. In: Cai, Y., Vetta, A. (eds.) WINE 2016. LNCS, vol. 10123, pp. 384–399. Springer, Heidelberg (2016). https://doi.org/10.1007/978-3-662-54110-4_27
Fain, B., Munagala, K., Shah, N.: Fair allocation of indivisible public goods. In: Proceedings of the 2018 ACM Conference on Economics and Computation, pp. 575–592 (2018). Extended version. arXiv:1805.03164
Faliszewski, P., Skowron, P., Slinko, A., Talmon, N.: Multiwinner voting: a new challenge for social choice theory. In: Endriss, U. (ed.) Trends in Computational Social Choice, pp. 27–47. AI Access (2017)
Farahani, R.Z., Hekmatfar, M. (eds.): Facility Location: Concepts, Models, Algorithms and Case Studies. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-7908-2151-2
Jiang, Z., Munagala, K., Wang, K.: Approximately stable committee selection. In: STOC-2020, pp. 463–472 (2020)
Lackner, M., Skowron, P.: Approval-based committee voting: axioms, algorithms, and applications. Technical report. arXiv:2007.01795 [cs.GT], arXiv.org (2020)
Magiera, K., Faliszewski, P.: Recognizing top-monotonic preference profiles in polynomial time. J. Artif. Intell. Res. 66, 57–84 (2019)
Mirrlees, J.: An exploration in the theory of optimal income taxation. Rev. Econ. Stud. 38, 175–208 (1971)
Osborne, J.M., Rubinstein, A.: A Course in Game Theory, vol. 1. The MIT Press, Cambridge (1994)
Peters, D., Skowron, P.: Proportionality and the limits of welfarism. In: EC-2020, pp. 793–794 (2020). Extended version. arXiv:1911.11747
Pierczyński, G., Skowron, P.: Core-stable committees under restricted domains (2021). https://doi.org/10.48550/ARXIV.2108.01987. https://arxiv.org/abs/2108.01987
Roberts, K.W.S.: Voting over income tax schedules. J. Public Econ. 8(3), 329–340 (1977)
Sánchez-Fernández, L., et al.: Proportional justified representation. In: Proceedings of the 31st AAAI Conference on Artificial Intelligence (AAAI-2017), pp. 670–676 (2017)
Skowron, P., Faliszewski, P., Lang, J.: Finding a collective set of items: from proportional multirepresentation to group recommendation. Artif. Intell. 241, 191–216 (2016)
Skowron, P., Lackner, M., Brill, M., Peters, D., Elkind, E.: Proportional rankings. In: IJCAI-2017, pp. 409–415 (2017)
Srinivasan, A.: Distributions on level-sets with applications to approximation algorithms. In: FOCS-2001, pp. 588–597 (2001)
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2022 The Author(s), under exclusive license to Springer Nature Switzerland AG
About this paper
Cite this paper
Pierczyński, G., Skowron, P. (2022). Core-Stable Committees Under Restricted Domains. In: Hansen, K.A., Liu, T.X., Malekian, A. (eds) Web and Internet Economics. WINE 2022. Lecture Notes in Computer Science, vol 13778. Springer, Cham. https://doi.org/10.1007/978-3-031-22832-2_18
Download citation
DOI: https://doi.org/10.1007/978-3-031-22832-2_18
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-031-22831-5
Online ISBN: 978-3-031-22832-2
eBook Packages: Computer ScienceComputer Science (R0)