{"type":"ScholarlyArticle","title":"Approval with Runoff","authors":[{"name":"Théo Delemazure","slug":"theo-delemazure","given":"Théo","family":"Delemazure","affiliation":"CNRS , Université Paris-Dauphine , Université PSL , LAMSADE"},{"name":"Jérôme Lang","slug":"jerome-lang","given":"Jérôme","family":"Lang","affiliation":"CNRS , Université Paris-Dauphine , Université PSL , LAMSADE"},{"name":"Jean-François Laslier","slug":"jean-francois-laslier","given":"Jean-François","family":"Laslier","affiliation":"CNRS , Paris School of Economics , Université PSL"},{"name":"M. Remzi Sanver","slug":"m-remzi-sanver","given":"M. Remzi","family":"Sanver","affiliation":"CNRS , Université Paris-Dauphine , Université PSL , LAMSADE"}],"abstract":"We define a family of runoff rules that work as follows: voters cast approval ballots over candidates; two finalists are selected; and the winner is decided by majority. With approval-type ballots, there are various ways to select the finalists. We leverage known approval-based committee rules and study the obtained runoff rules from an axiomatic point of view. Then we analyze the outcome of these rules on single-peaked profiles, and on real data.","doi":"10.24963/ijcai.2022/33","url":"https://ijcai.org/proceedings/2022/33","pdf":"https://ijcai.org/proceedings/2022/0033.pdf","markdown":"https://ijcai.org/proceedings/2022/33.md","bibtex":"https://ijcai.org/proceedings/2022/bibtex/33","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":33,"pages":{"first":230,"last":236},"keywords":["Agent-based and Multi-agent Systems: Computational Social Choice"],"videos":[{"label":"Video #1","url":"https://slideslive.com/38987001","length_sec":89,"provider":"slideslive"},{"label":"Video #2","url":"https://slideslive.com/38985144","length_sec":715,"provider":"slideslive"}],"references":[{"position":1,"raw":"[Bouveret et al., 2019] Sylvain Bouveret, Renaud Blanch, Antoinette Baujard, Franc ¸ois Durand, Herrade Igersheim, Jérôme Lang, Annick Laruelle, Jean-Franc ¸ois Laslier, Is- abelle Lebon, and Vincent Merlin. 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