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arXiv · 2609.32545

Connected EF1 Allocations Exist in Discrete Chore Cutting

Ankang Sun·Bo Li
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Abstract

In this paper, we prove the existence of an envy-free up to one item (EF1) division for a discrete chore. Our approach builds on the powerful framework of Simmons-Su, which leverages Sperner's lemma to guarantee the existence of a simplex corresponding to a sequence of similar fractional divisions, ensuring that each agent is satisfied with a different bundle. Bilò et al. [2022] introduced a rounding technique that converts the fractional divisions into a connected integral EF1 division for goods when there are at most four agents, and this method was later extended by Igarashi [2023] to accommodate any number of agents. However, these rounding techniques for goods do not directly apply to chores because the definitions of EF1 differ in the two settings. To overcome this asymmetry, we modify the existing rounding techniques and show that connected EF1 divisions exist for a discrete chore.

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Ankang Sun, Bo Li. 2026-09-26. Connected EF1 Allocations Exist in Discrete Chore Cutting. https://arxiv.org/abs/2609.32545

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