Generalized Parameter Lifting: Finer Abstractions for Parametric Markov Chains
This program is tentative and subject to change.
Parametric Markov chains (pMCs) are Markov chains (MCs) with symbolic probabilities. A pMC encodes a family of MCs, where each member is obtained by replacing parameters with constants. The parameters allow encoding dependencies between transitions, which sets pMCs apart from interval MCs. The verification problem for pMCs asks whether each MC in the corresponding family satisfies a given temporal specification. The state-of-the-art approach for this problem is parameter lifting (PL)—an abstraction-refinement loop that abstracts the pMC to a non-parametric model analyzed with standard probabilistic model checking techniques. This paper presents two key improvements to tackle the main limitations of PL. First, we introduce generalized parameter lifting (GPL) to lift various restrictive assumptions made by PL. Second, we present a big-step transformation algorithm that reduces parameter dependencies in pMCs and, therefore, results in tighter approximations. Experiments show that GPL is widely applicable and that the big-step transformation accelerates pMC verification by up to orders of magnitude.
This program is tentative and subject to change.
Tue 28 OctDisplayed time zone: Chennai, Kolkata, Mumbai, New Delhi change
14:00 - 15:30 | |||
14:00 30mPaper | Data Structures for Finite Downsets of Natural Vectors: Theory and Practice ATVA Papers Michaël Cadilhac , Vanessa Fluegel University of Antwerp, Antwerp, Belgium, Guillermo A. Perez University of Antwerp, Shrisha Rao University of Antwerp, Antwerp, Belgium | ||
14:30 30mPaper | Generalized Parameter Lifting: Finer Abstractions for Parametric Markov Chains ATVA Papers Linus Heck Radboud University, Tim Quatmann RWTH Aachen University, Jip Spel RWTH Aachen University, Joost-Pieter Katoen RWTH Aachen University, Sebastian Junges Radboud University | ||
15:00 30mPaper | Antarbhukti: Verifying Correctness of PLC Software during System Evolution ATVA Papers Pre-print | ||