PRISM is a probabilistic model checker, a formal verification software tool for the modelling and analysis of systems that exhibit probabilistic behaviour. [1] One source of such systems is the use of randomization, for example in communication protocols like Bluetooth and FireWire, or in security protocols such as Crowds and Onion routing. Stochastic behaviour also arises in many other computer systems, for example due to equipment failures, unbreliable sensors and actuators, or unpredictable communication delays. PRISM has been used to analyse a diverse range of applications, from robot planning to computer network performance analysis to biochemical reaction networks. [2]
PRISM can be used to analyse several different types of probabilistic models, including discrete-time Markov chains, continuous-time Markov chains, Markov decision processes and probabilistic extensions of the timed automata formalism. It also supports probabilistic models with partial observability and notions of epistemic uncertainty. Properties to be verified against these models are expressed in probabilistic extensions of temporal logic, such as PCTL. PRISM's companion tool PRISM-games [3] provides analysis for stochastic games.
Development of PRISM is led from the University of Oxford. The project originally began at the University of Birmingham. The tool is open-source software, released under the GNU General Public License. PRISM has been selected for the Google Summer of Code programme in 2013 and 2014. The tool and its creators have won several awards: the [2024 ETAPS Test-of-Time Tool Award] and the [HVC 2016 Award].
Queueing theory is the mathematical study of waiting lines, or queues. A queueing model is constructed so that queue lengths and waiting time can be predicted. Queueing theory is generally considered a branch of operations research because the results are often used when making business decisions about the resources needed to provide a service.
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The following outline is provided as an overview of and topical guide to machine learning:
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Lenore D. Zuck is an Israeli-American computer scientist whose research involves formal methods in software engineering, as well as information privacy. She is a research professor of computer science at the University of Illinois Chicago.
Kim Guldstrand Larsen R is a Danish scientist and professor of computer science at Aalborg University, Denmark. His field of research includes modeling, validation and verification, performance analysis, and synthesing of real-time, embedded, and cyber-physical systems utilizing and contributing to concurrency theory and model checking. Within this domain, he has been instrumental in the invention and continuous development of one of the most widely used verification tools, and has received several awards and honors for his work.