Skip to main content
Log in

On the Complexity of Pareto-Optimal Nash and Strong Equilibria

  • Published:
Theory of Computing Systems Aims and scope Submit manuscript

Abstract

We consider the computational complexity of coalitional solution concepts in scenarios related to load balancing such as anonymous and congestion games. In congestion games, Pareto-optimal Nash and strong equilibria, which are resilient to coalitional deviations, have recently been shown to yield significantly smaller inefficiency. Unfortunately, we show that several problems regarding existence, recognition, and computation of these concepts are hard, even in seemingly special classes of games. In anonymous games with constant number of strategies, we can efficiently recognize a state as Pareto-optimal Nash or strong equilibrium, but deciding existence for a game remains hard. In the case of player-specific singleton congestion games, we show that recognition and computation of both concepts can be done efficiently. In addition, in these games there are always short sequences of coalitional improvement moves to Pareto-optimal Nash and strong equilibria that can be computed efficiently.

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

Access this article

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

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3

Similar content being viewed by others

References

  1. Ackermann, H., Röglin, H., Vöcking, B.: On the impact of combinatorial structure on congestion games. J. ACM 55(6), 25 (2008)

    MathSciNet  Google Scholar 

  2. Andelman, N., Feldman, M., Mansour, Y.: Strong price of anarchy. Games Econ. Behav. 65(2), 289–317 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  3. Aumann, R.: Acceptable points in general cooperative n-person games. In: Contributions to the Theory of Games IV. Annals of Mathematics Study, vol. 40, pp. 287–324. Princeton University Press, Princeton (1959)

    Google Scholar 

  4. Blonski, M.: Anonymous games with binary actions. Games Econ. Behav. 28, 171–180 (1999)

    Article  MathSciNet  MATH  Google Scholar 

  5. Blonski, M.: Characterization of pure strategy equilibria in finite anonymous games. J. Math. Econ. 34(2), 225–233 (2000)

    Article  MathSciNet  MATH  Google Scholar 

  6. Brandt, F., Fischer, F., Holzer, M.: Symmetries and the complexity of pure Nash equilibrium. J. Comput. Syst. Sci. 75(3), 163–177 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  7. Chien, S., Sinclair, A.: Strong and Pareto price of anarchy in congestion games. In: Proc. 36th Intl. Coll. Automata, Languages and Programming (ICALP), pp. 279–291 (2009)

    Chapter  Google Scholar 

  8. Daskalakis, C., Papadimitriou, C.: Computing equilibria in anonymous games. In: Proc. 48th Symp. Foundations of Computer Science (FOCS), pp. 83–93 (2007)

    Google Scholar 

  9. Daskalakis, C., Papadimitriou, C.: Discretized multinomial distributions and Nash equilibria in anonymous games. In: Proc. 49th Symp. Foundations of Computer Science (FOCS), pp. 25–34 (2008)

    Google Scholar 

  10. Dunkel, J., Schulz, A.: On the complexity of pure-strategy Nash equilibria in congestion and local-effect games. Math. Oper. Res. 33(4), 851–868 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  11. Fabrikant, A., Papadimitriou, C., Talwar, K.: The complexity of pure Nash equilibria. In: Proc. 36th Symp. Theory of Computing (STOC), pp. 604–612 (2004)

    Google Scholar 

  12. Fiat, A., Kaplan, H., Levy, M., Olonetsky, S.: Strong price of anarchy for machine load balancing. In: Proc. 34th Intl. Coll. Automata, Languages and Programming (ICALP), pp. 583–594 (2007)

    Chapter  Google Scholar 

  13. Gottlob, G., Greco, G., Scarcello, F.: Pure Nash equilibria: hard and easy games. J. Artif. Intell. Res. 24, 195–220 (2005)

    MathSciNet  Google Scholar 

  14. Harks, T., Hoefer, M., Klimm, M., Skopalik, A.: Computing pure Nash and strong equilibria in bottleneck congestion games. In: Proc. 18th European Symposium on Algorithms (ESA), vol. 2, pp. 29–38 (2010)

    Google Scholar 

  15. Harks, T., Klimm, M., Möhring, R.: Strong Nash equilibria in games with the lexicographical improvement property. In: Proc. 5th Intl. Workshop Internet & Network Economics (WINE), pp. 463–470 (2009)

    Chapter  Google Scholar 

  16. Hoefer, M., Skopalik, A.: On the complexity of Pareto-optimal Nash and strong equilibria. In: Proc. 3rd Intl. Symp. Algorithmic Game Theory (SAGT), pp. 312–322 (2010)

    Chapter  Google Scholar 

  17. Holzman, R., Law-Yone, N.: Strong equilibrium in congestion games. Games Econ. Behav. 21(1–2), 85–101 (1997)

    Article  MathSciNet  MATH  Google Scholar 

  18. Konishi, H., Le Breton, M., Weber, S.: Equilibria in a model with partial rivalry. J. Econ. Theory 72(1), 225–237 (1997)

    Article  MathSciNet  MATH  Google Scholar 

  19. Mas-Colell, A., Whinston, M., Green, J.: Microeconomic Theory. Oxford University Press, London (1995)

    MATH  Google Scholar 

  20. Meyers, C.: Network flow problems and congestion games: complexity and approximation results. Ph.D. thesis, MIT (2006)

  21. Milchtaich, I.: Congestion games with player-specific payoff functions. Games Econ. Behav. 13(1), 111–124 (1996)

    Article  MathSciNet  MATH  Google Scholar 

  22. Rosenthal, R.: A class of games possessing pure-strategy Nash equilibria. Int. J. Game Theory 2, 65–67 (1973)

    Article  MATH  Google Scholar 

  23. Rozenfeld, O., Tennenholtz, M.: Strong and correlated strong equilibria in monotone congestion games. In: Proc. 2nd Intl. Workshop Internet & Network Economics (WINE), pp. 74–86 (2006)

    Chapter  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Martin Hoefer.

Additional information

A preliminary version of this paper appeared in the proceedings of the 3rd International Symposium on Algorithmic Game Theory (SAGT 2010) [16].

M. Hoefer was supported by DFG through UMIC Research Center at RWTH Aachen University and grant Ho 3831/3-1.

A. Skopalik was supported in part by the German Israeli Foundation (GIF) under contract 877/05.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Hoefer, M., Skopalik, A. On the Complexity of Pareto-Optimal Nash and Strong Equilibria. Theory Comput Syst 53, 441–453 (2013). https://doi.org/10.1007/s00224-012-9433-0

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00224-012-9433-0

Keywords

Navigation