Strategy-proofness of the randomized Condorcet voting system
In this paper, we study the strategy-proofness properties of the randomized Condorcet voting system (RCVS). Discovered at several occasions independently, the RCVS is arguably the natural extension of the Condorcet method to cases where a deterministic Condorcet winner does not exists. Indeed, it se...
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| Format: | Article |
| Language: | English |
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Springer Berlin Heidelberg
2017
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| Online Access: | http://hdl.handle.net/1721.1/107673 https://orcid.org/0000-0002-0832-9236 |
| _version_ | 1826207291462909952 |
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| author | Hoang, Le Nguyen |
| author2 | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science |
| author_facet | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Hoang, Le Nguyen |
| author_sort | Hoang, Le Nguyen |
| collection | MIT |
| description | In this paper, we study the strategy-proofness properties of the randomized Condorcet voting system (RCVS). Discovered at several occasions independently, the RCVS is arguably the natural extension of the Condorcet method to cases where a deterministic Condorcet winner does not exists. Indeed, it selects the always-existing and essentially unique Condorcet winner of lotteries over alternatives. Our main result is that, in a certain class of voting systems based on pairwise comparisons of alternatives, the RCVS is the only one to be Condorcet-proof. By Condorcet-proof, we mean that, when a Condorcet winner exists, it must be selected and no voter has incentives to misreport his preferences. We also prove two theorems about group-strategy-proofness. On one hand, we prove that there is no group-strategy-proof voting system that always selects existing Condorcet winners. On the other hand, we prove that, when preferences have a one-dimensional structure, the RCVS is group-strategy-proof. |
| first_indexed | 2024-09-23T13:47:21Z |
| format | Article |
| id | mit-1721.1/107673 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T13:47:21Z |
| publishDate | 2017 |
| publisher | Springer Berlin Heidelberg |
| record_format | dspace |
| spelling | mit-1721.1/1076732022-09-28T16:12:01Z Strategy-proofness of the randomized Condorcet voting system Hoang, Le Nguyen Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology. Laboratory for Information and Decision Systems Hoang, Le Nguyen In this paper, we study the strategy-proofness properties of the randomized Condorcet voting system (RCVS). Discovered at several occasions independently, the RCVS is arguably the natural extension of the Condorcet method to cases where a deterministic Condorcet winner does not exists. Indeed, it selects the always-existing and essentially unique Condorcet winner of lotteries over alternatives. Our main result is that, in a certain class of voting systems based on pairwise comparisons of alternatives, the RCVS is the only one to be Condorcet-proof. By Condorcet-proof, we mean that, when a Condorcet winner exists, it must be selected and no voter has incentives to misreport his preferences. We also prove two theorems about group-strategy-proofness. On one hand, we prove that there is no group-strategy-proof voting system that always selects existing Condorcet winners. On the other hand, we prove that, when preferences have a one-dimensional structure, the RCVS is group-strategy-proof. 2017-03-23T19:02:25Z 2017-12-03T06:00:04Z 2017-02 2015-09 2017-03-08T04:40:12Z Article http://purl.org/eprint/type/JournalArticle 0176-1714 1432-217X http://hdl.handle.net/1721.1/107673 Hoang, Lê Nguyên. “Strategy-Proofness of the Randomized Condorcet Voting System.” Social Choice and Welfare 48, no. 3 (February 13, 2017): 679–701. https://orcid.org/0000-0002-0832-9236 en http://dx.doi.org/10.1007/s00355-017-1031-2 Social Choice and Welfare Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. Springer-Verlag Berlin Heidelberg application/pdf Springer Berlin Heidelberg Springer Berlin Heidelberg |
| spellingShingle | Hoang, Le Nguyen Strategy-proofness of the randomized Condorcet voting system |
| title | Strategy-proofness of the randomized Condorcet voting system |
| title_full | Strategy-proofness of the randomized Condorcet voting system |
| title_fullStr | Strategy-proofness of the randomized Condorcet voting system |
| title_full_unstemmed | Strategy-proofness of the randomized Condorcet voting system |
| title_short | Strategy-proofness of the randomized Condorcet voting system |
| title_sort | strategy proofness of the randomized condorcet voting system |
| url | http://hdl.handle.net/1721.1/107673 https://orcid.org/0000-0002-0832-9236 |
| work_keys_str_mv | AT hoanglenguyen strategyproofnessoftherandomizedcondorcetvotingsystem |