{"type":"ScholarlyArticle","title":"Preserving Consistency in Multi-Issue Liquid Democracy","authors":[{"name":"Rachael Colley","slug":"rachael-colley","given":"Rachael","family":"Colley","affiliation":"IRIT , University of Toulouse , France"},{"name":"Umberto Grandi","slug":"umberto-grandi","given":"Umberto","family":"Grandi","affiliation":"IRIT , University of Toulouse , France"}],"abstract":"Liquid democracy bridges the gap between direct and representative democracy by allowing agents to vote directly on an issue or delegate to a trusted voter. Yet, when applied to votes on multiple interconnected issues, liquid democracy can lead agents to submit inconsistent votes. Two approaches are possible to maintain consistency: either modify the voters' ballots by ignoring problematic delegations, or resolve all delegations and make changes to the final votes of the agents. We show that rules based on minimising such changes are NP-complete. We propose instead to elicit and apply the agents' priorities over the delegated issues, designing and analysing two algorithms that find consistent votes from the agents' delegations in polynomial time.","doi":"10.24963/ijcai.2022/29","url":"https://ijcai.org/proceedings/2022/29","pdf":"https://ijcai.org/proceedings/2022/0029.pdf","markdown":"https://ijcai.org/proceedings/2022/29.md","bibtex":"https://ijcai.org/proceedings/2022/bibtex/29","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":29,"pages":{"first":201,"last":207},"keywords":["Agent-based and Multi-agent Systems: Algorithmic Game Theory","Agent-based and Multi-agent Systems: Computational Social Choice","Agent-based and Multi-agent Systems: Coordination and Cooperation"],"videos":[{"label":"Video #1","url":"https://slideslive.com/38986859","length_sec":88,"provider":"slideslive"},{"label":"Video #2","url":"https://slideslive.com/38985002","length_sec":338,"provider":"slideslive"}],"references":[{"position":1,"raw":"[Armstrong and Larson, 2021] Ben Armstrong and Kate Larson. 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