Computer Science – Logic in Computer Science
Scientific paper
2009-03-13
LMCS 5 (2:7) 2009
Computer Science
Logic in Computer Science
The paper is accepted for LMCS
Scientific paper
10.2168/LMCS-5(2:7)2009
We investigate logics and equivalence relations that capture the qualitative behavior of Markov Decision Processes (MDPs). We present Qualitative Randomized CTL (QRCTL): formulas of this logic can express the fact that certain temporal properties hold over all paths, or with probability 0 or 1, but they do not distinguish among intermediate probability values. We present a symbolic, polynomial time model-checking algorithm for QRCTL on MDPs. The logic QRCTL induces an equivalence relation over states of an MDP that we call qualitative equivalence: informally, two states are qualitatively equivalent if the sets of formulas that hold with probability 0 or 1 at the two states are the same. We show that for finite alternating MDPs, where nondeterministic and probabilistic choices occur in different states, qualitative equivalence coincides with alternating bisimulation, and can thus be computed via efficient partition-refinement algorithms. On the other hand, in non-alternating MDPs the equivalence relations cannot be computed via partition-refinement algorithms, but rather, they require non-local computation. Finally, we consider QRCTL*, that extends QRCTL with nested temporal operators in the same manner in which CTL* extends CTL. We show that QRCTL and QRCTL* induce the same qualitative equivalence on alternating MDPs, while on non-alternating MDPs, the equivalence arising from QRCTL* can be strictly finer. We also provide a full characterization of the relation between qualitative equivalence, bisimulation, and alternating bisimulation, according to whether the MDPs are finite, and to whether their transition relations are finitely-branching.
Alfaro Luca de
Chatterjee Krishnendu
Faella Marco
Legay Axel
No associations
LandOfFree
Qualitative Logics and Equivalences for Probabilistic Systems does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Qualitative Logics and Equivalences for Probabilistic Systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Qualitative Logics and Equivalences for Probabilistic Systems will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-229326