# Computational Complexity of Computing a Quasi-Proper Equilibrium

```@inproceedings{Hansen2021ComputationalCO,
title={Computational Complexity of Computing a Quasi-Proper Equilibrium},
author={Kristoffer Arnsfelt Hansen and Troels Bjerre Lund},
booktitle={FCT},
year={2021}
}```
• Published in FCT 9 July 2021
• Computer Science
We study the computational complexity of computing or approximating a quasi-proper equilibrium for a given finite extensive form game of perfect recall. We show that the task of computing a symbolic quasiproper equilibrium is PPAD-complete for two-player games. For the case of zero-sum games we obtain a polynomial time algorithm based on Linear Programming. For general n-player games we show that computing an approximation of a quasi-proper equilibrium is FIXPa-complete. Towards our results for…

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