Very Justified Envy

Adam Hamdan

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arXiv · 2609.07682

Very Justified Envy

Adam Hamdan

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Abstract

This paper studies the intensity of priority violations in matching markets. An agent is said to have very justified envy if she prefers another agent's match to her own and her priority advantage for the object exceeds $k$ ranks. I show that unless $k$ is prohibitively large, Pareto efficiency is incompatible with the elimination of very justified envy. A simple generalization of Deferred Acceptance and Immediate Acceptance is proposed and shown to eliminate very justified envy for any $k$. In simulations of random matching markets, I find that modest relaxations to justified envy can yield significant improvements in assignment ranks.

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Adam Hamdan. 2026-09-07. Very Justified Envy. https://arxiv.org/abs/2609.07682

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