Branching-time model-checking of probabilistic pushdown automata

In this paper we study complexity of the model-checking problem for probabilistic pushdown automata (pPDA) and qualitative fragments of two branching-time logics PCTL∗ and PECTL∗. We prove that this problem is in 2-EXPTIME for pPDA and qualitative PCTL∗. Consequently, we prove that model-checking of stateless pPDA (pBPA) and both qualitative PCTL∗ and qualitative PECTL∗ is 2-EXPTIME-hard. These results combined with results of several other papers give us that the model-checking problem for pPDA (and also for pBPA) and both qualitative PCTL∗ and qualitative PECTL∗ is 2-EXPTIME-complete. Finally, we survey known results on model-checking of pPDA and branching-time logics.