Probabilistic Timed Automata with Clock-Dependent Probabilities

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10506)


Probabilistic timed automata are classical timed automata extended with discrete probability distributions over edges. We introduce clock-dependent probabilistic timed automata, a variant of probabilistic timed automata in which transition probabilities can depend linearly on clock values. Clock-dependent probabilistic timed automata allow the modelling of a continuous relationship between time passage and the likelihood of system events. We show that the problem of deciding whether the maximum probability of reaching a certain location is above a threshold is undecidable for clock-dependent probabilistic timed automata. On the other hand, we show that the maximum and minimum probability of reaching a certain location in clock-dependent probabilistic timed automata can be approximated using a region-graph-based approach.



The inspiration for cdPTA arose from a discussion with Patricia Bouyer on the corner-point abstraction. Thanks also to Holger Hermanns, who expressed interest in a cdPTA-like formalism in a talk at Dagstuhl Seminar 14441.


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.Dipartimento di InformaticaUniversity of TurinTurinItaly

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