Nothing Special   »   [go: up one dir, main page]

Skip to main content
Log in

Existence of Solution of Minimax Inequalities, Equilibria in Games and Fixed Points Without Convexity and Compactness Assumptions

  • Published:
Journal of Optimization Theory and Applications Aims and scope Submit manuscript

Abstract

This paper characterizes the existence of equilibria in minimax inequalities without assuming any form of quasiconcavity of functions and convexity or compactness of choice sets. A new condition, called “local dominatedness property”, is shown to be necessary and further, under some mild continuity condition, sufficient for the existence of equilibrium. We then apply the basic result obtained in the paper to generalize the existing theorems on the existence of saddle points, fixed points, and coincidence points without convexity or compactness assumptions. As an application, we also characterize the existence of pure strategy Nash equilibrium in games with discontinuous and non-quasiconcave payoff functions and nonconvex and/or noncompact strategy spaces.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2

Similar content being viewed by others

Notes

  1. Banach Fixed Point Theorem: Let (K,d) be a complete metric space and let f:KK be a d-contraction (d∈[0,1[). Then, f has a unique fixed point.

  2. Brouwer–Schauder–Tychonoff Fixed Point Theorem: Let K be a nonempty, compact and convex subset of a locally convex Hausdorff space, and let f:KK be a continuous function. Then the set of fixed points of f is compact and nonempty.

  3. Halpern–Bergman Fixed Point Theorem: Let K be a nonempty, compact and convex subset of a locally convex Hausdorff space X, and let C:KX be an inward pointing upper semicontinuous mapping with nonempty, closed and convex values. Then C has a fixed point.

  4. Kakutani–Fan–Glicksberg Fixed Point Theorem: Let K be a subset nonempty, compact and convex of a locally convex Hausdorff space, and let C:KK have closed graph and nonempty and convex values. Then the set of fixed points of C is nonempty and compact.

References

  1. Fan, K.: Minimax inequality and applications. In: Shisha, O. (ed.) Inequality, vol. III, pp. 103–113. Academic Press, New York (1972)

    Google Scholar 

  2. Aubin, J.P., Ekeland, I.: Applied Nonlinear Analysis. Wiley, New York (1984)

    MATH  Google Scholar 

  3. Lignola, M.B.: Ky fan inequalities and Nash equilibrium points without semicontinuity and compactness. J. Optim. Theory Appl. 94, 137–145 (1997)

    Article  MathSciNet  MATH  Google Scholar 

  4. Ding, X.P., Tan, K.K.: A minimax inequality with application to existence of equilibrium points and fixed point theorems. Colloque Math. 63, 233–274 (1992)

    MathSciNet  MATH  Google Scholar 

  5. Georgiev, P.G., Tanaka, T.: Vector-Valued Set-Valued variants of ky fan’s inequality. J. Nonlinear Convex Anal. 1, 245–254 (2000)

    MathSciNet  MATH  Google Scholar 

  6. Tian, G., Zhou, Z.: Quasi-Inequalities without the concavity assumption. J. Math. Anal. Appl. 172, 289–299 (1993)

    Article  MathSciNet  MATH  Google Scholar 

  7. Nessah, R., Larbani, M.: g-Maximum equality. In: Takahashi, W., Tanaka, T. (eds.) Nonlinear Analysis and Convex Analysis, pp. 391–400. Yokohama Publishers, Yokohama (2004)

    Google Scholar 

  8. Nessah, R., Chu, C.: Quasivariational equation. Math. Inequal. Appl. 7, 149–160 (2004)

    MathSciNet  MATH  Google Scholar 

  9. Simons, S.: Two function minimax theorem and variational inequalities for functions on compact and noncompact sets, with some comments on Fixed-Point theorems. Proc. Symp. Pure Math. 45, 377–392 (1986)

    Article  MathSciNet  Google Scholar 

  10. Yu, J., Yuan, X.Z.: The study of Pareto equilibria for multiobjective games by fixed point theorems and ky fan minimax inequality methods. Research report, no 1/95, Department of institute of mathematics, Guizhou Institute of technology, China (1995)

  11. Yuan, X.Z.: KKM principal, Ky Fan minimax inequalities and fixed point theorems. Nonlinear World 2, 131–169 (1995)

    MathSciNet  MATH  Google Scholar 

  12. Ansari, Q.H., Lin, Y.C., Yao, J.C.: General KKM theorem with applications to minimax and variational inequalities. J. Optim. Theory Appl. 104, 41–57 (2000)

    Article  MathSciNet  MATH  Google Scholar 

  13. Ansari, Q.H., Wong, N.C., Yao, J.C.: The existence of nonlinear inequalities. Appl. Math. Lett. 12, 89–92 (1999)

    Article  MathSciNet  MATH  Google Scholar 

  14. Ding, X.P., Park, S.: Existence of solutions for nonlinear inequalities in G-Convex spaces. Appl. Math. Lett. 15, 735–741 (1998)

    Article  MathSciNet  Google Scholar 

  15. Iusem, A.N., Soca, W.: New existence results for equilibrium problems. Nonlinear Anal. 54, 621–635 (2003)

    Article  Google Scholar 

  16. Lin, L.J.: Applications of a fixed point theorem in G-Convex space. Nonlinear Anal. 46, 601–608 (2001)

    Article  MathSciNet  MATH  Google Scholar 

  17. Lin, L.J., Ansari, Q.H., Yu, Z.T., Lai, L.P.: Fixed point and maximal element theorems with applications to abstract economies and minimax inequalities. J. Math. Anal. Appl. 284, 656–671 (2003)

    Article  MathSciNet  MATH  Google Scholar 

  18. Lin, L.J., Ansari, L.J.: Collective fixed points and maximal elements with applications to abstract economies. J. Math. Anal. Appl. 296, 455–472 (2004)

    Article  MathSciNet  MATH  Google Scholar 

  19. Lin, L.J., Chang, T.H.: S-KKM theorems, saddle points and minimax inequalities. Nonlinear Anal. 34, 73–86 (1998)

    Article  MathSciNet  MATH  Google Scholar 

  20. Lin, L.J., Park, S.: On some generalized Quasi-Equilibrium problems. J. Math. Anal. Appl. 224, 167–181 (1998)

    Article  MathSciNet  MATH  Google Scholar 

  21. Baye, M.R., Tian, G., Zhou, J.: Characterizations of the existence of equilibria in games with discontinuous and Non-Quasiconcave payoffs. Rev. Econ. Stud. 60, 935–948 (1993)

    Article  MathSciNet  MATH  Google Scholar 

  22. Aliprantis, C.B., Border, K.C.: Infinite Dimensional Analysis. Springer, New York (1994)

    MATH  Google Scholar 

  23. Kakutani, S.: A generalization of Bouwer’s fixed point theorem. Duke Math. J. 8, 457–459 (1941)

    Article  MathSciNet  Google Scholar 

  24. Nash, J.F.: Noncooperative games. Ann. Math. 54, 286–295 (1951)

    Article  MathSciNet  MATH  Google Scholar 

  25. Debreu, G.: A social equilibrium existence theorem. In: Proceedings of the National Academy of Sciences of the USA, vol. 38 (1952)

  26. Reny, J.P.: On the existence of pure and mixed strategy Nash equilibria in discontinuous games. Econometrica 67, 1029–1056 (1999)

    Article  MathSciNet  MATH  Google Scholar 

  27. Dasgupta, P., Maskin, E.: The existence of equilibrium in discontinuous economic games, I: Theory. Rev. Econ. Stud. 53, 1–26 (1986)

    Article  MathSciNet  MATH  Google Scholar 

  28. Nishimura, K., Friedman, J.: Existence of Nash equilibriumin n-Person games without Quasi-Concavity. Int. Econ. Rev. 22, 637–648 (1981)

    Article  MathSciNet  MATH  Google Scholar 

  29. Rosen, J.B.: Existence and uniqueness of equilibrium point for concave n-Person games. Econometrica 33, 520–534 (1965)

    Article  MathSciNet  MATH  Google Scholar 

  30. Yao, J.C.: Nash equilibria in n-Person games without convexity. Appl. Math. Lett. 5, 67–69 (1992)

    Article  MATH  Google Scholar 

Download references

Acknowledgements

The authors would like to thank the two anonymous referees for insightful comments which have substantially improved the quality of the paper.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Rabia Nessah.

Additional information

Communicated by Suliman Saleh Al-Homidan.

Financial support from the National Natural Science Foundation of China (NSFC-70773073) and the Program to Enhance Scholarly and Creative Activities at Texas A&M University as well as from Cheung Kong Scholars Program at the Ministry of Education of China is gratefully acknowledged.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Nessah, R., Tian, G. Existence of Solution of Minimax Inequalities, Equilibria in Games and Fixed Points Without Convexity and Compactness Assumptions. J Optim Theory Appl 157, 75–95 (2013). https://doi.org/10.1007/s10957-012-0176-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10957-012-0176-5

Keywords

Navigation