{"type":"ScholarlyArticle","title":"Diversity of Extensions in Abstract Argumentation","authors":[{"name":"Johannes K. Fichte","slug":"johannes-k-fichte","given":"Johannes K.","family":"Fichte","affiliation":""},{"name":"Markus Hecher","slug":"markus-hecher","given":"Markus","family":"Hecher","affiliation":""},{"name":"Yasir Mahmood","slug":"yasir-mahmood","given":"Yasir","family":"Mahmood","affiliation":""},{"name":"Zhengjun Wang","slug":"zhengjun-wang","given":"Zhengjun","family":"Wang","affiliation":""}],"abstract":"Argumentation is an important topic of AI for modeling and reasoning about arguments. In abstract argumentation, we consider directed graphs, so-called argumentation frameworks (AF), that express conflicts between arguments. The semantics is defined\r\nby the notion of extensions, which are sets of arguments that satisfy particular relationship conditions in the AF. Usually, standard reasoning in argumentation do not reveal how far apart extensions are.\r\nWe introduce a quantitative notion of diversity of extensions based on the symmetric-difference and provide a systematic complexity classification. Intuitively, diversity captures whether extensions of a framework (accepted viewpoints) differ only marginally or represent fundamentally incompatible sets of arguments. We study whether an AF admits k-diverse extensions, admits k-diverse extensions covering specific arguments, and to compute the largest k for which an AF admits k-diverse extensions. We outline a prototype and provide an evaluation for computing diversity levels.","doi":"10.24963/ijcai.2026/428","url":"https://ijcai.org/proceedings/2026/428","pdf":"https://ijcai.org/proceedings/2026/0428.pdf","markdown":"https://ijcai.org/proceedings/2026/428.md","bibtex":"https://ijcai.org/proceedings/2026/bibtex/428","volume":{"slug":"2026","title":"Proceedings of the Thirty-Fifth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2026","url":"https://ijcai.org/proceedings/2026/","year":2026,"location":"Bremen, Germany","dates":"15-21 August 2026","editors":"Diego Calvanese","isbn":"978-1-956792-09-6","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2026"},"section":"Knowledge Representation and Reasoning","track":"Main Track","number":428,"pages":{"first":3846,"last":3854},"keywords":["Knowledge Representation and Reasoning: Argumentation","Knowledge Representation and Reasoning: Computational complexity of reasoning"],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}