Short sequences of improvement moves lead to approximate equilibria in constraint satisfaction games

Ioannis Caragiannis (1) , Angelo Fanelli (2) , Nick Gravin (3)

1 CTI - Computer Technology Institute
2 CREM - Centre de recherche en économie et management
3 Microsoft Research [Redmond]

We present an algorithm that computes approximate pure Nash equilibria in a broad class of constraint satisfaction games that generalize the well-known cut and party affiliation games. Our results improve previous ones by Bhalgat et al. (EC 10) in terms of the obtained approximation guarantee. More importantly, our algorithm identifies a polynomially-long sequence of improvement moves from any initial state to an approximate equilibrium in these games. The existence of such short sequences is an interesting structural property which, to the best of our knowledge, was not known before. Our techniques adapt and extend our previous work for congestion games (FOCS 11) but the current analysis is considerably simpler.

Mots clés: Simulation; modeling; constraint satisfaction games

Domaines: Economies et finances; Complexité [cs.CC]; Intelligence artificielle [cs.AI]

Ioannis Caragiannis, Angelo Fanelli, Nick Gravin. Short sequences of improvement moves lead to approximate equilibria in constraint satisfaction games: 7th International Symposium, SAGT 2014, Haifa, Israel, September 30 – October 2, 2014. Proceedings. Ron Lavi. Algorithmic Game Theory, Springer Berlin Heidelberg, pp.49-60, 2014, Lecture Notes in Computer Science, 978-3-662-44802-1. ⟨10.1007/978-3-662-44803-8_5⟩. ⟨hal-01104061⟩