2026-07-20T06:00:12Z https://drops.dagstuhl.de/oai

oai:drops-oai.dagstuhl.de:3880 2024-03-06T10:34:35Z ddc:004 open_access

Bisimilarity of Probabilistic Pushdown Automata Forejt, Vojtech Jancar, Petr Kiefer, Stefan Worrell, James bisimilarity probabilistic systems pushdown automata We study the bisimilarity problem for probabilistic pushdown automata (pPDA) and subclasses thereof. Our definition of pPDA allows both probabilistic and non-deterministic branching, generalising the classical notion of pushdown automata (without epsilon-transitions). Our first contribution is a general construction that reduces checking bisimilarity of probabilistic transition systems to checking bisimilarity of non-deterministic transition systems. This construction directly yields decidability of bisimilarity for pPDA, as well as an elementary upper bound for the bisimilarity problem on the subclass of probabilistic basic process algebras, i.e., single-state pPDA. We further show that, with careful analysis, the general reduction can be used to prove an EXPTIME upper bound for bisimilarity of probabilistic visibly pushdown automata. Here we also provide a matching lower bound, establishing EXPTIME-completeness. Finally we prove that deciding bisimilarity of probabilistic one-counter automata, another subclass of pPDA, is PSPACE-complete. Here we use a more specialised argument to obtain optimal complexity bounds. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Vojtech Forejt and Petr Jancar and Stefan Kiefer and James Worrell 2012 Is Part Of LIPIcs, Volume 18, IARCS Annual Conference on Foundations of Software Technology and Theoretical Computer Science (FSTTCS 2012) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.FSTTCS.2012.448 urn:nbn:de:0030-drops-38800 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.FSTTCS.2012.448 eng https://creativecommons.org/licenses/by/3.0/legalcode