## Computing Equilibria in Multi-Player Games (2004)

Venue: | In Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms (SODA |

Citations: | 51 - 3 self |

### BibTeX

@INPROCEEDINGS{Papadimitriou04computingequilibria,

author = {Christos H. Papadimitriou and Tim Roughgarden},

title = {Computing Equilibria in Multi-Player Games},

booktitle = {In Proceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms (SODA},

year = {2004},

pages = {82--91},

publisher = {SIAM}

}

### Years of Citing Articles

### OpenURL

### Abstract

We initiate the systematic study of algorithmic issues involved in finding equilibria (Nash and correlated) in games with a large number of players; such games, in order to be computationally meaningful, must be presented in some succinct, game-specific way. We develop a general framework for obtaining polynomial-time algorithms for optimizing over correlated equilibria in such settings, and show how it can be applied successfully to symmetric games (for which we actually find an exact polytopal characterization), graphical games, and congestion games, among others. We also present complexity results implying that such algorithms are not possible in certain other such games. Finally, we present a polynomial-time algorithm, based on quantifier elimination, for finding a Nash equilibrium in symmetric games when the number of strategies is relatively small.

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