# 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} }

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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