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In this article, we consider generalized Nash games where the associated constraint map is not necessarily self. The classical Nash equilibrium may not exist for such games and therefore we introduce the notion of best approximate solution…

Optimization and Control · Mathematics 2022-04-05 Asrifa Sultana , Shivani Valecha

In an epsilon-Nash equilibrium, a player can gain at most epsilon by changing his behaviour. Recent work has addressed the question of how best to compute epsilon-Nash equilibria, and for what values of epsilon a polynomial-time algorithm…

Computer Science and Game Theory · Computer Science 2015-03-20 John Fearnley , Paul W. Goldberg , Rahul Savani , Troels Bjerre Sørensen

We study the problem of computing approximate Nash equilibria of bimatrix games, in a setting where players initially know their own payoffs but not the payoffs of the other player. In order for a solution of reasonable quality to be found,…

Computer Science and Game Theory · Computer Science 2013-02-18 Paul Goldberg , Arnoud Pastink

We propose the first loss function for approximate Nash equilibria of normal-form games that is amenable to unbiased Monte Carlo estimation. This construction allows us to deploy standard non-convex stochastic optimization techniques for…

Computer Science and Game Theory · Computer Science 2024-04-16 Ian Gemp , Luke Marris , Georgios Piliouras

We show that the problem of finding an {\epsilon}-approximate Nash equilibrium in an anonymous game with seven pure strategies is complete in PPAD, when the approximation parameter {\epsilon} is exponentially small in the number of players.

Computer Science and Game Theory · Computer Science 2014-12-19 Xi Chen , David Durfee , Anthi Orfanou

In an $\epsilon$-Nash equilibrium, a player can gain at most $\epsilon$ by unilaterally changing his behaviour. For two-player (bimatrix) games with payoffs in $[0,1]$, the best-known$\epsilon$ achievable in polynomial time is 0.3393. In…

Computer Science and Game Theory · Computer Science 2014-10-02 Argyrios Deligkas , John Fearnley , Rahul Savani , Paul Spirakis

Nearly a decade ago, Azrieli and Shmaya introduced the class of $\lambda$-Lipschitz games in which every player's payoff function is $\lambda$-Lipschitz with respect to the actions of the other players. They showed that such games admit…

Computer Science and Game Theory · Computer Science 2021-07-09 Paul W. Goldberg , Matthew J. Katzman

A fundamental shortcoming of the concept of Nash equilibrium is its computational intractability: approximating Nash equilibria in normal-form games is PPAD-hard. In this paper, inspired by the ideas of smoothed analysis, we introduce a…

Computer Science and Game Theory · Computer Science 2024-07-23 Constantinos Daskalakis , Noah Golowich , Nika Haghtalab , Abhishek Shetty

Establishing the existence of Nash equilibria for partially observed stochastic dynamic games is known to be quite challenging, with the difficulties stemming from the noisy nature of the measurements available to individual players…

Systems and Control · Computer Science 2018-06-06 Naci Saldi , Tamer Basar , Maxim Raginsky

We study the existence and computation of Nash equilibria in concave games where the players' admissible strategies are subject to shared coupling constraints. Under playerwise concavity of constraints, we prove existence of Nash…

Computer Science and Game Theory · Computer Science 2026-02-09 Philip Jordan , Maryam Kamgarpour

This paper investigates the convergence time of log-linear learning to an $\epsilon$-efficient Nash equilibrium in potential games, where an efficient Nash equilibrium is defined as the maximizer of the potential function. Previous…

Multiagent Systems · Computer Science 2026-01-13 Anna Maddux , Reda Ouhamma , Maryam Kamgarpour

We prove that for any constant $k$ and any $\epsilon<1$, there exist bimatrix win-lose games for which every $\epsilon$-WSNE requires supports of cardinality greater than $k$. To do this, we provide a graph-theoretic characterization of…

Computer Science and Game Theory · Computer Science 2015-04-15 Yogesh Anbalagan , Hao Huang , Shachar Lovett , Sergey Norin , Adrian Vetta , Hehui Wu

We study the asymptotic organization among many optimizing individuals interacting in a suitable "moderate" way. We justify this limiting game by proving that its solution provides approximate Nash equilibria for large but finite player…

Optimization and Control · Mathematics 2021-12-20 Franco Flandoli , Maddalena Ghio , Giulia Livieri

We consider structural and algorithmic questions related to the Nash dynamics of weighted congestion games. In weighted congestion games with linear latency functions, the existence of (pure Nash) equilibria is guaranteed by potential…

Computer Science and Game Theory · Computer Science 2011-11-14 Ioannis Caragiannis , Angelo Fanelli , Nick Gravin , Alexander Skopalik

In this work, we present a novel characterization of approximate Nash equilibria in a class of convex games over the simplex. To achieve this, we regularize the utility functions using the Shannon entropy term, connect the solutions to the…

Optimization and Control · Mathematics 2025-07-18 Tatiana Tatarenko , S. Rasoul Etesami

In this paper, we aim to design a distributed approximate algorithm for seeking Nash equilibria of an aggregative game. Due to the local set constraints of each player, projectionbased algorithms have been widely employed for solving such…

Optimization and Control · Mathematics 2021-08-30 Gehui Xu , Guanpu Chen , Hongsheng Qi , Yiguang Hong

We conjecture that PPAD has a PCP-like complete problem, seeking a near equilibrium in which all but very few players have very little incentive to deviate. We show that, if one assumes that this problem requires exponential time, several…

Computational Complexity · Computer Science 2025-09-08 Yakov Babichenko , Christos Papadimitriou , Aviad Rubinstein

We show that there is a polynomial-time approximation scheme for computing Nash equilibria in anonymous games with any fixed number of strategies (a very broad and important class of games), extending the two-strategy result of Daskalakis…

Computer Science and Game Theory · Computer Science 2016-11-15 Constantinos Daskalakis , Christos H. Papadimitriou

In this paper, I prove that existence of pure-strategy Nash equilibrium in games with infinitely many players is equivalent to the axiom of choice.

Logic · Mathematics 2023-06-06 Conrad Kosowsky

We consider a stochastic tournament game in which each player is rewarded based on her rank in terms of the completion time of her own task and is subject to cost of effort. When players are homogeneous and the rewards are purely rank…

Optimization and Control · Mathematics 2018-11-02 Erhan Bayraktar , Jakša Cvitanić , Yuchong Zhang