Abstract
We present a formalization of probabilistic timed automata (PTA) in which we try to follow the formula “MDP + TA = PTA” as far as possible: our work starts from existing formalizations of Markov decision processes (MDP) and timed automata (TA) and combines them modularly. We prove the fundamental result for probabilistic timed automata: the region construction that is known from timed automata carries over to the probabilistic setting. In particular, this allows us to prove that minimum and maximum reachability probabilities can be computed via a reduction to MDP model checking, including the case where one wants to disregard unrealizable behavior.
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Notes
- 1.
We use the same notions as in [8]. Soundness: for every abstract run, there is a concrete instantiation. Completeness: every concrete run can be abstracted.
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Acknowledgments
We want to thank David Parker and Gethin Norman for clarifying our understanding of PTA model checking w.r.t. divergence. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 713999 - Matryoshka).
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Wimmer, S., Hölzl, J. (2018). MDP + TA = PTA: Probabilistic Timed Automata, Formalized (Short Paper). In: Avigad, J., Mahboubi, A. (eds) Interactive Theorem Proving. ITP 2018. Lecture Notes in Computer Science(), vol 10895. Springer, Cham. https://doi.org/10.1007/978-3-319-94821-8_35
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DOI: https://doi.org/10.1007/978-3-319-94821-8_35
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