Tim Quatmann
YOU?
Author Swipe
View article: Computing Expected Visiting Times and Stationary Distributions in Markov Chains: Fast and Accurate
Computing Expected Visiting Times and Stationary Distributions in Markov Chains: Fast and Accurate Open
We study the accurate and efficient computation of the expected number of times each state is visited in discrete- and continuous-time Markov chains. To obtain sound accuracy guarantees efficiently, we lift interval iteration, optimistic v…
View article: Compositional Reasoning for Parametric Probabilistic Automata
Compositional Reasoning for Parametric Probabilistic Automata Open
We establish an assume-guarantee (AG) framework for compositional reasoning about multi-objective queries in parametric probabilistic automata (pPA) - an extension to probabilistic automata (PA), where transition probabilities are function…
View article: What is the best algorithm for MDP model checking?
What is the best algorithm for MDP model checking? Open
Computing reachability probabilities and expected rewards for Markov decision processes is a core feature of probabilistic model checkers. Value iteration (VI) is the predominantly implemented approach but occasionally yields vastly incorr…
View article: Generalized Parameter Lifting: Finer Abstractions for Parametric Markov Chains
Generalized Parameter Lifting: Finer Abstractions for Parametric Markov Chains Open
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 tr…
View article: Fixed Point Certificates for Reachability and Expected Rewards in MDPs
Fixed Point Certificates for Reachability and Expected Rewards in MDPs Open
The possibility of errors in human-engineered formal verification software, such as model checkers, poses a serious threat to the purpose of these tools. An established approach to mitigate this problem are certificates -- lightweight, eas…
View article: Fixed Point Certificates for Reachability and Expected Rewards in MDPs
Fixed Point Certificates for Reachability and Expected Rewards in MDPs Open
The possibility of errors in human-engineered formal verification software, such as model checkers, poses a serious threat to the purpose of these tools. An established approach to mitigate this problem are certificates —lightweight, easy-…
View article: Tools at the Frontiers of Quantitative Verification
Tools at the Frontiers of Quantitative Verification Open
Contains fulltext : 317297.pdf (Publisher’s version ) (Open Access)
View article: Tools at the Frontiers of Quantitative Verification
Tools at the Frontiers of Quantitative Verification Open
The analysis of formal models that include quantitative aspects such as timing or probabilistic choices is performed by quantitative verification tools. Broad and mature tool support is available for computing basic properties such as expe…
View article: Parameter synthesis for Markov models: covering the parameter space
Parameter synthesis for Markov models: covering the parameter space Open
Markov chain analysis is a key technique in formal verification. A practical obstacle is that all probabilities in Markov models need to be known. However, system quantities such as failure rates or packet loss ratios, etc. are often not—o…
View article: Accurately Computing Expected Visiting Times and Stationary Distributions in Markov Chains
Accurately Computing Expected Visiting Times and Stationary Distributions in Markov Chains Open
We study the accurate and efficient computation of the expected number of times each state is visited in discrete- and continuous-time Markov chains. To obtain sound accuracy guarantees efficiently, we lift interval iteration and topologic…
View article: Accurately Computing Expected Visiting Times and Stationary Distributions in Markov Chains
Accurately Computing Expected Visiting Times and Stationary Distributions in Markov Chains Open
We study the accurate and efficient computation of the expected number of times each state is visited in discrete- and continuous-time Markov chains. To obtain sound accuracy guarantees efficiently, we lift interval iteration and topologic…
View article: A Spectrum of Approximate Probabilistic Bisimulations
A Spectrum of Approximate Probabilistic Bisimulations Open
This paper studies various notions of approximate probabilistic bisimulation on labeled Markov chains (LMCs). We introduce approximate versions of weak and branching bisimulation, as well as a notion of ε-perturbed bisimulation that relate…
View article: Verification of Multi-Objective Markov Models: Replication Package
Verification of Multi-Objective Markov Models: Replication Package Open
Contains benchmarks, execution scripts, log files, and the Storm version exercised for the experiments given in Chapter 9 of the work Verification of Multi-Objective Markov Models. List of contents: storm-package.zip: contains the Storm ve…
View article: Verification of Multi-Objective Markov Models: Replication Package
Verification of Multi-Objective Markov Models: Replication Package Open
Contains benchmarks, execution scripts, log files, and the Storm version exercised for the experiments given in Chapter 9 of the work Verification of Multi-Objective Markov Models. List of contents: storm-package.zip: contains the Storm ve…
View article: Parameter Synthesis for Markov Models: Prophesy and model files
Parameter Synthesis for Markov Models: Prophesy and model files Open
This artefact contains the Prophesy tool and all model files used for the evaluation in Sect. 11 of the paper "Parameter Synthesis for Markov Models". Further information can be found in the ARTEFACT.md.
View article: What is the Best Algorithm for MDP Model Checking? Replication Package
What is the Best Algorithm for MDP Model Checking? Replication Package Open
This artefact allows to review and replicate the experiments from the paper What is the Best Algorithm for MDP Model Checking?. The package contains all original logfiles and the scripts that extract the relevant data from those logs to ge…
View article: Parameter Synthesis for Markov Models: Prophesy and model files
Parameter Synthesis for Markov Models: Prophesy and model files Open
This artefact contains the Prophesy tool and all model files used for the evaluation in Sect. 11 of the paper "Parameter Synthesis for Markov Models". Further information can be found in the ARTEFACT.md.
View article: What is the Best Algorithm for MDP Model Checking? Replication Package
What is the Best Algorithm for MDP Model Checking? Replication Package Open
This artefact allows to review and replicate the experiments from the paper What is the Best Algorithm for MDP Model Checking?. The package contains all original logfiles and the scripts that extract the relevant data from those logs to ge…
View article: A Practitioner's Guide to MDP Model Checking Algorithms
A Practitioner's Guide to MDP Model Checking Algorithms Open
Model checking undiscounted reachability and expected-reward properties on Markov decision processes (MDPs) is key for the verification of systems that act under uncertainty. Popular algorithms are policy iteration and variants of value it…
View article: A Practitioner's Guide to MDP Model Checking Algorithms (Artefact)
A Practitioner's Guide to MDP Model Checking Algorithms (Artefact) Open
This artefact allows to review and replicate the experiments from the TACAS'23 paper A Practitioner's Guide to MDP Model Checking Algorithms. The package contains all original logfiles and the scripts that extract the relevant data from th…
View article: A Practitioner's Guide to MDP Model Checking Algorithms (Artefact)
A Practitioner's Guide to MDP Model Checking Algorithms (Artefact) Open
This artefact allows to review and replicate the experiments from the TACAS'23 paper A Practitioner's Guide to MDP Model Checking Algorithms. The package contains all original logfiles and the scripts that extract the relevant data from th…
View article: A Practitioner’s Guide to MDP Model Checking Algorithms
A Practitioner’s Guide to MDP Model Checking Algorithms Open
Model checking undiscounted reachability and expected-reward properties on Markov decision processes (MDPs) is key for the verification of systems that act under uncertainty. Popular algorithms are policy iteration and variants of value it…
View article: Under-Approximating Expected Total Rewards in POMDPs
Under-Approximating Expected Total Rewards in POMDPs Open
We consider the problem: is the optimal expected total reward to reach a goal state in a partially observable Markov decision process (POMDP) below a given threshold? We tackle this -- generally undecidable -- problem by computing under-ap…
View article: Under-Approximating Expected Total Rewards in POMDPs
Under-Approximating Expected Total Rewards in POMDPs Open
We consider the problem: is the optimal expected total reward to reach a goal state in a partially observable Markov decision process (POMDP) below a given threshold? We tackle this—generally undecidable—problem by computing under-approxim…
View article: The probabilistic model checker Storm
The probabilistic model checker Storm Open
We present the probabilistic model checker Storm . Storm supports the analysis of discrete- and continuous-time variants of both Markov chains and Markov decision processes. Storm has three major distinguishing features. It supports multip…
View article: Multi-objective Optimization of Long-run Average and Total Rewards
Multi-objective Optimization of Long-run Average and Total Rewards Open
This paper presents an efficient procedure for multi-objective model checking of long-run average reward (aka: mean pay-off) and total reward objectives as well as their combination. We consider this for Markov automata, a compositional mo…
View article: On Correctness, Precision, and Performance in Quantitative Verification
On Correctness, Precision, and Performance in Quantitative Verification Open
Quantitative verification tools compute probabilities, expected rewards, or steady-state values for formal models of stochastic and timed systems. Exact results often cannot be obtained efficiently, so most tools use floating-point arithme…
View article: Markov Automata with Multiple Objectives: Supplemental Material
Markov Automata with Multiple Objectives: Supplemental Material Open
This data set contains benchmark files for multi-objective model checking of Markov Automata with Storm.
View article: Markov Automata with Multiple Objectives: Supplemental Material
Markov Automata with Multiple Objectives: Supplemental Material Open
This data set contains benchmark files for multi-objective model checking of Markov Automata with Storm.
View article: Multi-objective Optimization of Long-run Average and Total Rewards
Multi-objective Optimization of Long-run Average and Total Rewards Open
This paper presents an efficient procedure for multi-objective model checking of long-run average reward (aka: mean pay-off) and total reward objectives as well as their combination. We consider this for Markov automata, a compositional mo…