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arXiv · 2608.04924

On the dimensions of correlated equilibrium polytopes of generic games

Jan Draisma·Linda Hoyer·Irem Portakal
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Abstract

In this paper, we study the dimension of the correlated equilibrium polytope of finite games. Under the oriented-matroid notion of genericity, we prove that if a generic game is not full-dimensional, then there exists a subgame whose correlated equilibrium polytope is affinely isomorphic to that of the original game. This settles and generalizes an earlier conjecture of Brandenburg, Hollering, and Portakal (2024). Moreover, we show that the existence of a correlated equilibrium whose slices are all non-zero implies that the correlated equilibrium polytope is either full-dimensional or a singleton.

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Jan Draisma, Linda Hoyer, Irem Portakal. 2026-08-05. On the dimensions of correlated equilibrium polytopes of generic games. https://arxiv.org/abs/2608.04924

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