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Related papers: Existence of EFX for Two Additive Valuations

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We study the fair allocation of indivisible goods among agents, with a focus on limiting envy. A central open question in this area is the existence of EFX allocations-allocations in which any envy of any agent i towards any agent j…

Computer Science and Game Theory · Computer Science 2025-12-29 Mahyar Afshinmehr , Arash Ashuri , Pouria Mahmoudkhan , Kurt Mehlhorn

In fair division problems, we are given a set $S$ of $m$ items and a set $N$ of $n$ agents with individual preferences, and the goal is to find an allocation of items among agents so that each agent finds the allocation fair. There are…

Envy-freeness up to any good (EFX) provides a strong and intuitive guarantee of fairness in the allocation of indivisible goods. But whether such allocations always exist or whether they can be efficiently computed remains an important open…

Computer Science and Game Theory · Computer Science 2020-12-16 Hadi Hosseini , Sujoy Sikdar , Rohit Vaish , Lirong Xia

We consider the problem of sharing a set of indivisible goods among agents in a fair manner, namely such that the allocation is envy-free up to any good (EFX). We focus on the problem of computing an EFX allocation in the two-agent case and…

Computer Science and Game Theory · Computer Science 2023-07-18 Paul W. Goldberg , Kasper Høgh , Alexandros Hollender

We study fair division of goods under the broad class of generalized assignment constraints. In this constraint framework, the sizes and values of the goods are agent-specific, and one needs to allocate the goods among the agents fairly…

Computer Science and Game Theory · Computer Science 2023-05-03 Siddharth Barman , Arindam Khan , Sudarshan Shyam , K. V. N. Sreenivas

We present a simple local search algorithm for computing EFX (envy-free up to any good) allocations of $m$ indivisible goods among $n$ agents with additive valuations. EFX is a compelling fairness notion, and whether such allocations always…

Computer Science and Game Theory · Computer Science 2025-10-08 Simina Brânzei

We consider the fair division problem of indivisible items. It is well-known that an envy-free allocation may not exist, and a relaxed version of envy-freeness, envy-freeness up to one item (EF1), has been widely considered. In an EF1…

Computer Science and Game Theory · Computer Science 2022-11-30 Xiaolin Bu , Zihao Li , Shengxin Liu , Jiaxin Song , Biaoshuai Tao

Fair division of indivisible goods is a very well-studied problem. The goal of this problem is to distribute $m$ goods to $n$ agents in a "fair" manner, where every agent has a valuation for each subset of goods. We assume general…

Computer Science and Game Theory · Computer Science 2020-02-25 Bhaskar Ray Chaudhury , Tellikepalli Kavitha , Kurt Mehlhorn , Alkmini Sgouritsa

The existence of EFX allocations is a major open problem in fair division, even for additive valuations. The current state of the art is that no setting where EFX allocations are impossible is known, and EFX is known to exist for ($i$)…

Computer Science and Game Theory · Computer Science 2021-03-02 Ben Berger , Avi Cohen , Michal Feldman , Amos Fiat

We study the fair division problem and the existence of allocations satisfying the fairness criterion envy-freeness up to any item (EFX). The existence of EFX allocations is a major open problem in the fair division literature. We consider…

Computational Engineering, Finance, and Science · Computer Science 2023-08-11 Xiaolin Bu , Jiaxin Song , Ziqi Yu

We study fair allocation of indivisible goods and chores among agents with \emph{lexicographic} preferences -- a subclass of additive valuations. In sharp contrast to the goods-only setting, we show that an allocation satisfying…

Computer Science and Game Theory · Computer Science 2022-03-15 Hadi Hosseini , Sujoy Sikdar , Rohit Vaish , Lirong Xia

Fair division is the problem of allocating a set of items among agents in a fair manner. One of the most sought-after fairness notions is envy-freeness (EF), requiring that no agent envies another's allocation. When items are indivisible,…

Computer Science and Game Theory · Computer Science 2024-07-25 Jinghan A Zeng , Ruta Mehta

Several fairness concepts have been proposed recently in attempts to approximate envy-freeness in settings with indivisible goods. Among them, the concept of envy-freeness up to any item (EFX) is arguably the closest to envy-freeness.…

Computer Science and Game Theory · Computer Science 2019-02-13 Ioannis Caragiannis , Nick Gravin , Xin Huang

We study fair division of divisible goods under generalized assignment constraints. Here, each good has an agent-specific value and size, and every agent has a budget constraint that limits the total size of the goods she can receive. Since…

Computer Science and Game Theory · Computer Science 2026-03-03 Siddharth Barman , Ioannis Caragiannis , Sudarshan Shyam

In this paper, we study how to fairly allocate a set of m indivisible chores to a group of n agents, each of which has a general additive cost function on the items. Since envy-free (EF) allocations are not guaranteed to exist, we consider…

Computer Science and Game Theory · Computer Science 2023-11-01 Shengwei Zhou , Xiaowei Wu

We study the problem of allocating a set of indivisible items among agents whose preferences include externalities. Unlike the standard fair division model, agents may derive positive or negative utility not only from items allocated…

Computer Science and Game Theory · Computer Science 2026-01-21 Frank Connor , Max Dupré la Tour , Vishnu V. Narayan , Šimon Schierreich

We study the problem of fairly allocating indivisible goods between groups of agents using the recently introduced relaxations of envy-freeness. We consider the existence of fair allocations under different assumptions on the valuations of…

Computer Science and Game Theory · Computer Science 2020-09-17 Maria Kyropoulou , Warut Suksompong , Alexandros A. Voudouris

We study the fair allocation of indivisible resources among agents. Most prior work focuses on fairness and/or efficiency among agents. However, the allocator, as the resource owner, may also be involved in many scenarios (e.g., government…

Computer Science and Game Theory · Computer Science 2025-06-10 Xiaolin Bu , Zihao Li , Shengxin Liu , Jiaxin Song , Biaoshuai Tao

We study the problem of fairly allocating a set of chores to a group of agents. The existence of envy-free up to any item (EFX) allocations is a long-standing open question for both goods and chores. We resolve this question by providing a…

Computer Science and Game Theory · Computer Science 2024-06-18 Vasilis Christoforidis , Christodoulos Santorinaios

We study an online fair division problem where a fixed number of goods arrive sequentially and must be allocated to a given set of agents. Once a good arrives, its true value for each agent is revealed, and it has to be immediately and…

Computer Science and Game Theory · Computer Science 2025-08-08 Themistoklis Melissourgos , Nicos Protopapas