{"type":"ScholarlyArticle","title":"Merge-and-Shrink Task Reformulation for Classical Planning","authors":[{"name":"Álvaro Torralba","slug":"alvaro-torralba","given":"Álvaro","family":"Torralba","affiliation":"Saarland University , Saarland Informatics Campus , Germany"},{"name":"Silvan Sievers","slug":"silvan-sievers","given":"Silvan","family":"Sievers","affiliation":"University of Basel , Switzerland"}],"abstract":"The performance of domain-independent planning systems heavily depends on how the planning task has been modeled. This makes task reformulation an important tool to get rid of unnecessary complexity and increase the robustness of planners with respect to the model chosen by the user. In this paper, we represent tasks as factored transition systems (FTS), and use the merge-and-shrink (M&S) framework for task reformulation for optimal and satisficing planning. We prove that the flexibility of the underlying representation makes the M&S reformulation methods more powerful than the counterparts based on the more popular finite-domain representation. We adapt delete-relaxation and M&S heuristics to work on the FTS representation and evaluate the impact of our reformulation.","doi":"10.24963/ijcai.2019/783","url":"https://ijcai.org/proceedings/2019/783","pdf":"https://ijcai.org/proceedings/2019/0783.pdf","markdown":"https://ijcai.org/proceedings/2019/783.md","bibtex":"https://ijcai.org/proceedings/2019/bibtex/783","volume":{"slug":"2019","title":"Proceedings of the Twenty-Eighth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2019","url":"https://ijcai.org/proceedings/2019/","year":2019,"location":"Macao","dates":"10-16 August 2019","editors":"Sarit Kraus","isbn":"978-0-9992411-4-1","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2019"},"section":"Planning and Scheduling","track":"Main track","number":783,"pages":{"first":5644,"last":5652},"keywords":["Planning and Scheduling: Planning Algorithms","Planning and Scheduling: Search in Planning and Scheduling","Planning and Scheduling: Planning and Scheduling"],"videos":[],"references":[{"position":1,"raw":"[Bacchus and Yang, 1994] Fahiem Bacchus and Qiang Yang. 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