{"type":"ScholarlyArticle","title":"Approximately EFX and fPO Allocations for Bivalued Chores","authors":[{"name":"Zehan Lin","slug":"zehan-lin","given":"Zehan","family":"Lin","affiliation":""},{"name":"Xiaowei Wu","slug":"xiaowei-wu","given":"Xiaowei","family":"Wu","affiliation":""},{"name":"Shengwei Zhou","slug":"shengwei-zhou","given":"Shengwei","family":"Zhou","affiliation":""}],"abstract":"We consider the computation for allocations of indivisible chores that are approximately EFX and fractional Pareto optimal (fPO). It has been shown that 3-EFX and fPO allocations for bi-valued instances always exist, where the cost of an item to an agent is either 1 or k (where k > 1), by rounding the (fractional) earning restricted equilibrium. In this work, we improve the approximation ratio to (2-1/k), while preserving the fractional Pareto optimality. Instead of rounding fractional equilibrium, our algorithm starts with the integral EF1 equilibrium for bi-valued chores and reallocates items until approximate EFX is achieved. We further improve our result for the case when k=2 and devise an algorithm that computes EFX and fPO allocations.","doi":"10.24963/ijcai.2025/440","url":"https://ijcai.org/proceedings/2025/440","pdf":"https://ijcai.org/proceedings/2025/0440.pdf","markdown":"https://ijcai.org/proceedings/2025/440.md","bibtex":"https://ijcai.org/proceedings/2025/bibtex/440","volume":{"slug":"2025","title":"Proceedings of the Thirty-Fourth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2025","url":"https://ijcai.org/proceedings/2025/","year":2025,"location":"Montreal, Canada","dates":"16-22 August 2025","editors":"James Kwok","isbn":"978-1-956792-06-5","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2025"},"section":"Game Theory and Economic Paradigms","track":"Main Track","number":440,"pages":{"first":3952,"last":3960},"keywords":["Game Theory and Economic Paradigms: GTEP: Fair division"],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}