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Related papers: Smoothed Complexity of 2-player Nash Equilibria

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Congestion games offer a primary model in the study of pure Nash equilibria in non-cooperative games, and a number of generalized models have been proposed in the literature. One line of generalization includes weighted congestion games, in…

Computer Science and Game Theory · Computer Science 2024-01-09 Kenjiro Takazawa

We characterize Nash equilibrium by postulating coherent behavior across varying games. Nash equilibrium is the only solution concept that satisfies the following axioms: (i) strictly dominant actions are played with positive probability,…

Theoretical Economics · Economics 2024-07-02 Florian Brandl , Felix Brandt

We present for every $n\ge4$ an $n$-player game in normal form with payoffs in $\{0,1,2\}$ that has a unique, fully mixed, Nash equilibrium in which all the probability weights are irradical (i.e., algebraic but not closed form expressible…

Computer Science and Game Theory · Computer Science 2025-07-15 Edan Orzech , Martin Rinard

Nash equilibrium is a central concept in game theory. Several Nash solvers exist, yet none scale to normal-form games with many actions and many players, especially those with payoff tensors too big to be stored in memory. In this work, we…

Computer Science and Game Theory · Computer Science 2022-02-07 Ian Gemp , Rahul Savani , Marc Lanctot , Yoram Bachrach , Thomas Anthony , Richard Everett , Andrea Tacchetti , Tom Eccles , János Kramár

Nash equilibrium} (NE) can be stated as a formal theorem on a multilinear form, free of game theory terminology. On the other hand, inspired by this formalism, we state and prove a {\it multilinear minimax theorem}, a generalization of von…

Computer Science and Game Theory · Computer Science 2024-01-01 Bahman Kalantari

Congestion games constitute an important class of games to model resource allocation by different users. As computing an exact or even an approximate pure Nash equilibrium is in general PLS-complete, Caragiannis et al. (2011) present a…

Computer Science and Game Theory · Computer Science 2020-08-03 Alexander Skopalik , Vipin Ravindran Vijayalakshmi

We consider a general-sum N-player linear-quadratic game with stochastic dynamics over a finite horizon and prove the global convergence of the natural policy gradient method to the Nash equilibrium. In order to prove the convergence of the…

Optimization and Control · Mathematics 2022-08-16 Ben Hambly , Renyuan Xu , Huining Yang

We derive Nash equilibria for a class of quadratic multi-leader-follower games using the nonsmooth best response function. To overcome the challenge of nonsmoothness, we pursue a smoothing approach resulting in a reformulation as a smooth…

Optimization and Control · Mathematics 2020-04-30 Michael Herty , Sonja Steffensen , Anna Thünen

An heuristic approach to compute strong Nash (Aumann) equilibria is presented. The method is based on differential evolution and three variants of a generative relation for strong Nash equilibria characterization. Numerical experiments…

Computer Science and Game Theory · Computer Science 2014-08-29 Noémi Gaskó , Rodica Ioana Lung , D. Dumitrescu

Computational aspects of solution notions such as Nash equilibrium have been extensively studied, including settings where the ultimate goal is to find an equilibrium that possesses some additional properties. Furthermore, in order to…

Computational Complexity · Computer Science 2023-05-09 Bruce M. Kapron , Koosha Samieefar

We study a general scenario of simultaneous contests that allocate prizes based on equal sharing: each contest awards its prize to all players who satisfy some contest-specific criterion, and the value of this prize to a winner decreases as…

Computer Science and Game Theory · Computer Science 2022-07-19 Edith Elkind , Abheek Ghosh , Paul W. Goldberg

We show that the existence of a computationally efficient calibration algorithm, with a low weak calibration rate, would imply the existence of an efficient algorithm for computing approximate Nash equilibria - thus implying the unlikely…

Computer Science and Game Theory · Computer Science 2012-02-23 Elad Hazan , Sham Kakade

Recent extensions to dynamic games of the well-known fictitious play learning procedure in static games were proved to globally converge to stationary Nash equilibria in two important classes of dynamic games (zero-sum and…

Computer Science and Game Theory · Computer Science 2022-07-08 Lucas Baudin , Rida Laraki

For a constant $\epsilon$, we prove a poly(N) lower bound on the (randomized) communication complexity of $\epsilon$-Nash equilibrium in two-player NxN games. For n-player binary-action games we prove an exp(n) lower bound for the…

Computer Science and Game Theory · Computer Science 2016-09-14 Yakov Babichenko , Aviad Rubinstein

In finite games mixed Nash equilibria always exist, but pure equilibria may fail to exist. To assess the relevance of this nonexistence, we consider games where the payoffs are drawn at random. In particular, we focus on games where a large…

Computer Science and Game Theory · Computer Science 2020-06-18 Ben Amiet , Andrea Collevecchio , Marco Scarsini , Ziwen Zhong

In this article we consider a special class of Nash equilibrium problems that cannot be reduced to a single player control problem. Problems of this type can be solved by a semi-smooth Newton method. Applying results from the established…

Optimization and Control · Mathematics 2018-11-09 Veronika Karl , Frank Pörner

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 quasi-proper equilibrium is…

Computer Science and Game Theory · Computer Science 2021-07-12 Kristoffer Arnsfelt Hansen , Troels Bjerre Lund

Many important real-world settings contain multiple players interacting over an unknown duration with probabilistic state transitions, and are naturally modeled as stochastic games. Prior research on algorithms for stochastic games has…

Computer Science and Game Theory · Computer Science 2021-02-19 Sam Ganzfried

We consider the problem of learning sparse polymatrix games from observations of strategic interactions. We show that a polynomial time method based on $\ell_{1,2}$-group regularized logistic regression recovers a game, whose Nash…

Machine Learning · Computer Science 2019-01-30 Asish Ghoshal , Jean Honorio

We formulate two-party policy competition as a two-player non-cooperative game, generalizing Lin et al.'s work (2021). Each party selects a real-valued policy vector as its strategy from a compact subset of Euclidean space, and a voter's…

Computer Science and Game Theory · Computer Science 2026-03-19 Chuang-Chieh Lin , Chi-Jen Lu , Po-An Chen , Chih-Chieh Hung