Method of equal shares

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The method of equal shares[1][2][3][4] is a proportional method of counting ballots that applies to participatory budgeting,[2] to committee elections,[3] and to simultaneous public decisions.[4][5] It can be used when the voters vote via approval ballots, ranked ballots or cardinal ballots. It works by dividing the available budget into equal parts that are assigned to each voter. The method is only allowed to use the budget share of a voter to implement projects that the voter voted for. It then repeatedly finds projects that can be afforded using the budget shares of the supporting voters. In contexts other than participatory budgeting, the method works by equally dividing an abstract budget of "voting power".[1]

In 2023, the method of equal shares was being used in a participatory budgeting program in the Polish city of Wieliczka.[6] The program, known as Green Million (Zielony Milion), was set to distribute 1 million złoty to ecological projects proposed by residents of the city. It was also used in a participatory budgeting program in the Swiss city of Aarau in 2023 (Stadtidee).[7]

  1. ^ a b Lackner, Martin; Skowron, Piotr (2023). Multi-Winner Voting with Approval Preferences. SpringerBriefs in Intelligent Systems. arXiv:2007.01795. doi:10.1007/978-3-031-09016-5. ISBN 978-3-031-09015-8. S2CID 244921148.
  2. ^ a b Peters, Dominik; Pierczyński, Grzegorz; Skowron, Piotr (2021). "Proportional Participatory Budgeting with Additive Utilities". Proceedings of the 2021 Conference on Neural Information Processing Systems. NeurIPS'21. arXiv:2008.13276.
  3. ^ a b Peters, Dominik; Skowron, Piotr (2020). "Proportionality and the Limits of Welfarism". Proceedings of the 21st ACM Conference on Economics and Computation. EC'20. pp. 793–794. arXiv:1911.11747. doi:10.1145/3391403.3399465. ISBN 9781450379755. S2CID 208291203.
  4. ^ a b Freeman, Rupert; Kahng, Anson; Pennock, David (2020). "Proportionality in Approval-Based Elections with a Variable Number of Winners". Proceedings of the Twenty-Ninth International Joint Conference on Artificial Intelligence. IJCAI'20. Vol. 1. pp. 132–138. doi:10.24963/ijcai.2020/19. ISBN 978-0-9992411-6-5. S2CID 211052991.
  5. ^ Conitzer, Vincent; Freeman, Rupert; Shah, Nisarg (2017). "Fair Public Decision Making". Proceedings of the 2017 ACM Conference on Economics and Computation. EC'17. pp. 629–646. arXiv:1611.04034. doi:10.1145/3033274.3085125. ISBN 9781450345279. S2CID 30188911.
  6. ^ "Zielony Milion - rusza nowatorski projekt BO w Wieliczce [WIDEO]". Głos24 (in Polish). 2023-03-09. Retrieved 2023-03-11.
  7. ^ Stadt Aarau. "Abstimmungsphase - Stadtidee Aarau". stadtidee.aarau.ch. Retrieved 2023-03-11.