{"type":"ScholarlyArticle","title":"Optimisation and Approximation in Abstract Argumentation: The Case of Stable Semantics","authors":[{"name":"Matthias Thimm","slug":"matthias-thimm","given":"Matthias","family":"Thimm","affiliation":"Artificial Intelligence Group , University of Hagen , Germany"}],"abstract":"We analyse two soft notions of stable extensions in abstract argumentation, one that weakens the requirement of having full range and one that weakens the requirement of conflict-freeness. We then consider optimisation problems over these two notions that represent optimisation variants of the credulous reasoning problem with stable semantics. We investigate the computational complexity of these two problems in terms of the complexity of solving the optimisation problem exactly and in terms of approximation complexity. We also present some  polynomial-time approximation algorithms for these optimisation problems and investigate their approximation quality experimentally.","doi":"10.24963/ijcai.2024/396","url":"https://ijcai.org/proceedings/2024/396","pdf":"https://ijcai.org/proceedings/2024/0396.pdf","markdown":"https://ijcai.org/proceedings/2024/396.md","bibtex":"https://ijcai.org/proceedings/2024/bibtex/396","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":"Knowledge Representation and Reasoning","track":"Main Track","number":396,"pages":{"first":3576,"last":3583},"keywords":["Knowledge Representation and Reasoning: KRR: Computational complexity of reasoning","Knowledge Representation and Reasoning: KRR: Argumentation"],"videos":[],"references":[{"position":1,"raw":"[Amgoud and Ben-Naim, 2013] Leila Amgoud and Jonathan Ben-Naim. 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