Title
Qualitative Determinacy and Decidability of Stochastic Games with Signals
Abstract
We consider the standard model of finite two-person zero-sum stochastic games with signals. We are interested in the existence of almost-surely winning or positively winning strategies, under reachability, safety, Buchi or co-Buchi winning objectives. We prove two qualitative determinacy results. First, in a reachability game either player $1$ can achieve almost-surely the reachability objective, or player 2 can ensure surely the complementary safety objective, or both players have positively winning strategies. Second, in a Buchi game if player 1 cannot achieve almost-surely the Buchi objective, then player 2 can ensure positively the complementary co-Buchi objective. We prove that players only need strategies with finite-memory, whose sizes range from no memory at all to doubly-exponential number of states, with matching lower bounds. Together with the qualitative determinacy results, we also provide fix-point algorithms for deciding which player has an almost-surely winning or a positively winning strategy and for computing the finite memory strategy. Complexity ranges from EXPTIME to 2-EXPTIME with matching lower bounds, and better complexity can be achieved for some special cases where one of the players is better informed than her opponent.
Year
DOI
Venue
2009
10.1109/LICS.2009.31
J. ACM
Keywords
Field
DocType
reachability objective,buchi game,qualitative determinacy,almost-surely winning,stochastic games,complementary co-buchi objective,better complexity,lower bound,buchi objective,reachability game,complementary safety objective,qualitative determinacy result,fixed point,stochastic processes,imperfect information,games,common sense reasoning,determinacy,standard model,signals,data mining
Discrete mathematics,Combinatorics,EXPTIME,Computer science,Commonsense reasoning,Stochastic process,Decidability,Reachability,Perfect information,Determinacy
Conference
Volume
Issue
ISSN
64
5
0004-5411
Citations 
PageRank 
References 
23
1.05
21
Authors
3
Name
Order
Citations
PageRank
Nathalie Bertrand125017.84
Blaise Genest230425.09
Hugo Gimbert324921.31