{"type":"ScholarlyArticle","title":"Bidirectional Heuristic Search: Expanding Nodes by a Lower Bound","authors":[{"name":"Shahaf Shperberg","slug":"shahaf-shperberg","given":"Shahaf","family":"Shperberg","affiliation":"Ben-Gurion University of the Negev , Be' er-Sheva , Israel"},{"name":"Ariel Felner","slug":"ariel-felner","given":"Ariel","family":"Felner","affiliation":"Ben-Gurion University of the Negev , Be' er-Sheva , Israel"},{"name":"Nathan Sturtevant","slug":"nathan-sturtevant","given":"Nathan","family":"Sturtevant","affiliation":"University of Alberta , Edmonton , Canada"},{"name":"Eyal Shimony","slug":"eyal-shimony","given":"Eyal","family":"Shimony","affiliation":"Ben-Gurion University of the Negev , Be' er-Sheva , Israel"},{"name":"Avi Hayoun","slug":"avi-hayoun","given":"Avi","family":"Hayoun","affiliation":"Ben-Gurion University of the Negev , Be' er-Sheva , Israel"}],"abstract":"Recent work on bidirectional search defined a lower bound on costs of paths between pairs of nodes, and introduced a new algorithm, NBS, which is based on this bound. Building on these results, we introduce DVCBS, a new algorithm that aims to to further reduce the number of expansions. Generalizing beyond specific algorithms, we then propose a method for enhancing heuristics by propagating such lower bounds (lb-propagation) between frontiers. This lb-propagation can be used in existing algorithms, often improving their performance, as well as making them \"well behaved\".","doi":"10.24963/ijcai.2020/664","url":"https://ijcai.org/proceedings/2020/664","pdf":"https://ijcai.org/proceedings/2020/0664.pdf","markdown":"https://ijcai.org/proceedings/2020/664.md","bibtex":"https://ijcai.org/proceedings/2020/bibtex/664","volume":{"slug":"2020","title":"Proceedings of the Twenty-Ninth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2020","url":"https://ijcai.org/proceedings/2020/","year":2020,"location":"Yokohama","dates":"January 2021 (postponed from 11-17 July 2020)","editors":"Christian Bessiere","isbn":"978-0-9992411-6-5","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2020"},"section":"Sister Conferences Best Papers","track":"Sister Conferences Best Papers","number":664,"pages":{"first":4775,"last":4779},"keywords":["Heuristic Search and Game Playing: Heuristic Search"],"videos":[{"label":"Video","url":"https://videos.ijcai20.org/25145/file_25145.m3u8","length_sec":285,"provider":"hls"}],"references":[{"position":1,"raw":"[Alcázar et al., 2020] Vidal Alcázar, Pat Riddle, and Mike Barley. 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