{"type":"ScholarlyArticle","title":"Selecting the Most Conflicting Pair of Candidates","authors":[{"name":"Théo Delemazure","slug":"theo-delemazure","given":"Théo","family":"Delemazure","affiliation":"CNRS , LAMSADE , Université Paris Dauphine -PSL"},{"name":"Łukasz Janeczko","slug":"ukasz-janeczko","given":"Łukasz","family":"Janeczko","affiliation":"AGH University"},{"name":"Andrzej Kaczmarczyk","slug":"andrzej-kaczmarczyk","given":"Andrzej","family":"Kaczmarczyk","affiliation":"AGH University"},{"name":"Stanisław Szufa","slug":"stanis-aw-szufa","given":"Stanisław","family":"Szufa","affiliation":"CNRS , LAMSADE , Université Paris Dauphine -PSL; AGH University"}],"abstract":"We study committee elections from a perspective of finding the most conflicting candidates, that is, candidates that imply the largest amount of conflict, as per voter preferences. By proposing basic axioms to capture this objective, we show that none of the prominent multiwinner voting rules meet them. Consequently, we design committee voting rules compliant with our desiderata, introducing conflictual voting rules. A subsequent deepened analysis sheds more light on how they operate. Our investigation identifies various aspects of conflict, for which we come up with relevant axioms and quantitative measures, which may be of independent interest. We support our theoretical study with experiments on both real-life and synthetic data.","doi":"10.24963/ijcai.2024/306","url":"https://ijcai.org/proceedings/2024/306","pdf":"https://ijcai.org/proceedings/2024/0306.pdf","markdown":"https://ijcai.org/proceedings/2024/306.md","bibtex":"https://ijcai.org/proceedings/2024/bibtex/306","volume":{"slug":"2024","title":"Proceedings of the Thirty-Third International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2024","url":"https://ijcai.org/proceedings/2024/","year":2024,"location":"Jeju, Korea","dates":"3-9 August 2024","editors":"Kate Larson","isbn":"978-1-956792-04-1","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2024"},"section":"Game Theory and Economic Paradigms","track":"Main Track","number":306,"pages":{"first":2766,"last":2773},"keywords":["Game Theory and Economic Paradigms: GTEP: Computational social choice"],"videos":[],"references":[{"position":1,"raw":"[Alcalde-Unzu and Vorsatz, 2013] J. Alcalde-Unzu and M. Vorsatz. Measuring the cohesiveness of preferences: An axiomatic analysis. Social Choice and Welfare, 41(4):965-988, 2013.","title":"Measuring the cohesiveness of preferences: An axiomatic analysis","authors":"J Alcalde-Unzu, M Vorsatz","year":"2013","venue":"Social Choice and Welfare","doi":null,"url":null,"internal_url":null},{"position":2,"raw":"[Alcalde-Unzu and Vorsatz, 2016] J. Alcalde-Unzu and M. Vorsatz. Do we agree? Measuring the cohesiveness of preferences. Theory and Decision, 80(2):313-339, 2016.","title":"Do we agree? Measuring the cohesiveness of preferences","authors":"J Alcalde-Unzu, M Vorsatz","year":"2016","venue":"Theory and Decision","doi":null,"url":null,"internal_url":null},{"position":3,"raw":"[Bouveret et al., 2018] S. Bouveret, R. Blanch, A. Baujard, F. Durand, H. Igersheim, J. Lang, A. Laruelle, J.-F. Laslier, I. Lebon, and V. Merlin. Voter autrement 2017 -online experiment. Dataset and companion article on Zenodo, July 2018.","title":"Voter autrement 2017 -online experiment","authors":"S Bouveret, R Blanch, A Baujard, F Durand, H Igersheim, J Lang, A Laruelle, J.-F Laslier, I Lebon, V Merlin","year":"2018","venue":"Dataset and companion article on Zenodo","doi":null,"url":null,"internal_url":null},{"position":4,"raw":"[Can et al., 2017] B. Can, A. Ozkes, and T. Storcken. Gener- alized measures of polarization in preferences. Technical report, HAL, 2017.","title":"Generalized measures of polarization in preferences","authors":"B Can, A Ozkes, T Storcken","year":"2017","venue":null,"doi":null,"url":null,"internal_url":null},{"position":5,"raw":"[Chamberlin and Courant, 1983] B. Chamberlin and P. Courant. Representative deliberations and representa- tive decisions: Proportional representation and the Borda rule. American Political Science Review, 77(3):718-733, 1983.","title":"Representative deliberations and representative decisions: Proportional representation and the Borda rule","authors":"B Chamberlin, P Courant","year":"1983","venue":"American Political Science Review","doi":null,"url":null,"internal_url":null},{"position":6,"raw":"[Colley et al., 2023] R. Colley, U. Grandi, C. Hidalgo, M. Macedo, and C. Navarrete. Measuring and control- ling divisiveness in rank aggregation. In Proceedings of IJCAI-2023, pages 2616-2623, 2023.","title":"Measuring and controlling divisiveness in rank aggregation","authors":"R Colley, U Grandi, C Hidalgo, M Macedo, C Navarrete","year":"2023","venue":"Proceedings of IJCAI-2023","doi":null,"url":null,"internal_url":"/proceedings/2023/291"},{"position":7,"raw":"[Debord, 1992] B. Debord. An axiomatic characterization of Borda's k-choice function. Social Choice and Welfare, 9(4):337-343, 1992.","title":"An axiomatic characterization of Borda's k-choice function","authors":"B Debord","year":"1992","venue":"Social Choice and Welfare","doi":null,"url":null,"internal_url":null},{"position":8,"raw":"[Delemazure and Bouveret, 2022] T. Delemazure and S. Bouveret. Voter autrement 2022 -online experiment (\"Un autre vote\"). Dataset and companion article on Zenodo, April 2022.","title":"Voter autrement 2022 -online experiment","authors":"T Delemazure, S Bouveret","year":"2022","venue":"Dataset and companion article on Zenodo","doi":null,"url":null,"internal_url":null},{"position":9,"raw":"[Delemazure et al., 2024] T. Delemazure, Ł. Janeczko, A. Kaczmarczyk, and S. Szufa. Selecting the most conflicting pair of candidates. Technical Report arXiv.2405.05870 [cs.GT, arXiv.org, 2024.","title":"Selecting the most conflicting pair of candidates","authors":"T Delemazure, Ł Janeczko, A Kaczmarczyk, S Szufa","year":"2024","venue":null,"doi":null,"url":null,"internal_url":null},{"position":10,"raw":"[Elkind et al., 2017a] E. Elkind, P. Faliszewski, J. Laslier, P. Skowron, A. Slinko, and N. Talmon. What do mul- tiwinner voting rules do? An experiment over the two- dimensional euclidean domain. In Proceedings of AAAI- 2017, pages 494-501, 2017.","title":"What do multiwinner voting rules do? An experiment over the two-dimensional euclidean domain","authors":"Elkind","year":"2017","venue":"Proceedings of AAAI-2017","doi":null,"url":null,"internal_url":null},{"position":11,"raw":"[Elkind et al., 2017b] E. Elkind, P. Faliszewski, P. Skowron, and A. Slinko. Properties of multiwinner voting rules. So- cial Choice and Welfare, 48(3):599-632, 2017.","title":"Properties of multiwinner voting rules","authors":"Elkind","year":"2017","venue":"Social Choice and Welfare","doi":null,"url":null,"internal_url":null},{"position":12,"raw":"[Faliszewski et al., 2017] P. Faliszewski, P. Skowron, A. Slinko, and N. Talmon. Multiwinner voting: A new challenge for social choice theory. In U. Endriss, editor, Trends in Computational Social Choice. AI Access Foundation, 2017.","title":"Multiwinner voting: A new challenge for social choice theory","authors":"P Faliszewski, P Skowron, A Slinko, N Talmon","year":"2017","venue":"Trends in Computational Social Choice","doi":null,"url":null,"internal_url":null},{"position":13,"raw":"[Faliszewski et al., 2019] P. Faliszewski, P. Skowron, S. Sz- ufa, and N. Talmon. Proportional representation in elec- tions: STV vs PAV. In Proceedings of AAMAS-2011, pages 1946-1948, 2019.","title":"Proportional representation in elections: STV vs PAV","authors":"P Faliszewski, P Skowron, S Szufa, N Talmon","year":"2019","venue":"Proceedings of AAMAS-2011","doi":null,"url":null,"internal_url":null},{"position":14,"raw":"[Faliszewski et al., 2023] P. Faliszewski, A. Kaczmarczyk, K. Sornat, S. Szufa, and T. W ąs. Diversity, agreement, and polarization in elections. In Proceedings of IJCAI-2023, pages 2684-2692, 2023.","title":"Diversity, agreement, and polarization in elections","authors":"P Faliszewski, A Kaczmarczyk, K Sornat, S Szufa, T W Ąs","year":"2023","venue":"Proceedings of IJCAI-2023","doi":null,"url":null,"internal_url":"/proceedings/2023/299"},{"position":15,"raw":"[Hashemi and Endriss, 2014] V. Hashemi and U. Endriss. Measuring diversity of preferences in a group. In Proceed- ings of ECAI-2014, pages 423-428, 2014.","title":"Measuring diversity of preferences in a group","authors":"V Hashemi, U Endriss","year":"2014","venue":"Proceedings of ECAI-2014","doi":null,"url":null,"internal_url":null},{"position":16,"raw":"[Kamishima, 2003] T. Kamishima. Nantonac collaborative filtering: Recommendation based on order responses. In Proceedings of KDD-03, pages 583-588, 2003.","title":"Nantonac collaborative filtering: Recommendation based on order responses","authors":"T Kamishima","year":"2003","venue":"Proceedings of KDD-03","doi":null,"url":null,"internal_url":null},{"position":17,"raw":"[Mattei and Walsh, 2013] N. Mattei and T. Walsh. Preflib: A library of preference data HTTP://PREFLIB.ORG. In Pro- ceedings of the 3rd International Conference on Algorith- mic Decision Theory (ADT 2013), Lecture Notes in Artifi- cial Intelligence. Springer, 2013.","title":"Preflib: A library of preference data HTTP://PREFLIB.ORG","authors":"N Mattei, T Walsh","year":"2013","venue":"Proceedings of the 3rd International Conference on Algorithmic Decision Theory (ADT 2013)","doi":null,"url":null,"internal_url":null},{"position":18,"raw":"[Monroe, 1995] Burt L. Monroe. Fully proportional rep- resentation. The American Political Science Review, 89(4):925-940, 1995.","title":"Fully proportional representation","authors":"L Burt, Monroe","year":"1995","venue":"The American Political Science Review","doi":null,"url":null,"internal_url":null},{"position":19,"raw":"[Peters et al., 2021] D. Peters, G. Pierczyński, and P. Skowron. Proportional participatory budgeting with additive utilities. In Proceedings of NeurIPS-2021, pages 12726-12737, 2021.","title":"Proportional participatory budgeting with additive utilities","authors":"D Peters, G Pierczyński, P Skowron","year":"2021","venue":"Proceedings of NeurIPS-2021","doi":null,"url":null,"internal_url":null},{"position":20,"raw":"[Skowron et al., 2017] P. Skowron, M. Lackner, M. Brill, D. Peters, and E. Elkind. Proportional rankings. In Pro- ceedings of IJCAI-2017, pages 409-415, 2017.","title":"Proportional rankings","authors":"P Skowron, M Lackner, M Brill, D Peters, E Elkind","year":"2017","venue":"Proceedings of IJCAI-2017","doi":null,"url":null,"internal_url":null},{"position":21,"raw":"[Skowron et al., 2019] P. Skowron, P. Faliszewski, and A. Slinko. Axiomatic characterization of committee scor- ing rules. Journal of Economic Theory, 180:244-273, 2019.","title":"Axiomatic characterization of committee scoring rules","authors":"P Skowron, P Faliszewski, A Slinko","year":"2019","venue":"Journal of Economic Theory","doi":null,"url":null,"internal_url":null}],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}