{"type":"ScholarlyArticle","title":"Let’s Agree to Agree: Targeting Consensus for Incomplete Preferences through Majority Dynamics","authors":[{"name":"Sirin Botan","slug":"sirin-botan","given":"Sirin","family":"Botan","affiliation":"UNSW Sydney"},{"name":"Simon Rey","slug":"simon-rey","given":"Simon","family":"Rey","affiliation":"Institute for Logic, Language and Computation (ILLC) , University of Amsterdam"},{"name":"Zoi Terzopoulou","slug":"zoi-terzopoulou","given":"Zoi","family":"Terzopoulou","affiliation":"LAMSADE , Université Paris Dauphine-PSL"}],"abstract":"We study settings in which agents with incomplete\r\npreferences need to make a collective decision. We\r\nfocus on a process of majority dynamics where issues\r\nare addressed one at a time and undecided\r\nagents follow the opinion of the majority. We assess\r\nthe effects of this process on various consensus\r\nnotions—such as the Condorcet winner—and show\r\nthat in the worst case, myopic adherence to the majority\r\ndamages existing consensus; yet, simulation\r\nexperiments indicate that the damage is often mild.\r\nWe also examine scenarios where the chair of the\r\ndecision process can control the existence (or the\r\nidentity) of consensus, by determining the order in\r\nwhich the issues are discussed.","doi":"10.24963/ijcai.2022/18","url":"https://ijcai.org/proceedings/2022/18","pdf":"https://ijcai.org/proceedings/2022/0018.pdf","markdown":"https://ijcai.org/proceedings/2022/18.md","bibtex":"https://ijcai.org/proceedings/2022/bibtex/18","volume":{"slug":"2022","title":"Proceedings of the Thirty-First International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2022","url":"https://ijcai.org/proceedings/2022/","year":2022,"location":"Vienna","dates":"23-29 July 2022","editors":"Luc De Raedt","isbn":"978-1-956792-00-3","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2022"},"section":"Agent-based and Multi-agent Systems","track":"Main Track","number":18,"pages":{"first":123,"last":129},"keywords":["Agent-based and Multi-agent Systems: Computational Social Choice"],"videos":[{"label":"Video #1","url":"https://slideslive.com/38987105","length_sec":78,"provider":"slideslive"},{"label":"Video #2","url":"https://slideslive.com/38985248","length_sec":555,"provider":"slideslive"}],"references":[{"position":1,"raw":"[Alcalde-Unzu and Vorsatz, 2011] Jorge Alcalde-Unzu and Marc Vorsatz. 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