Specification and Verification of Agent-based Models using Computer Aided Formal Verification
Supervisors
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Abstract
Agent-based Modelling (ABM) is a unique paradigm for studying complex systems wherein individual agents are explicitly modelled and interact with each other as part of a synthetic population. Within an agent-based model, each agent individually assesses its situation and makes potentially randomised decisions according to a set of internal rules. Note that agents may be heterogeneous, possessing different properties which may cause them to behave differently. By employing an agent-based model, one may hope to understand how global, or macroscopic, properties of a complex system may emerge from the collective behaviour of individuals. In particular, agent-based models allow practitioners to model real-world systems at extremely high fidelity, by taking into account many small details. However, this individual-based view on a global system naturally leads to a great computational overhead. As a result, it becomes challenging to carry out verification, validation, and analysis of agent-based models, and therefore reason about their correctness.In this project, we will focus on addressing this shortcoming. More specifically, this project will focus on finding computationally succinct representations of agent-based models which can be combined with techniques from formal verification and probabilistic model checking in order verify and reason about the properties of agent-based models.
In short, the main goals of this project include:
A. To formally describe agent-based models using a mathematical framework (e.g., finite dynamical systems, graph theory and Markov chains). B. Develop techniques to transform a formal ABM into probabilistic timed automata (PTAs) or discrete-time Markov chains (DTMCs) for formal verification using the PRISM model checker. C. Explore and implement state-space reduction techniques and demonstrate applications for industrial scale agent-based models.
Familiarity with PRISM, Computer-Aided Formal Verification, Probabilistic Model Checking. Desirable Prerequisites: Machine Learning.
[1] Laubenbacher, R., Jarrah, A.S., Mortveit, H.S., Ravi, S. (2012). Agent Based Modeling, Mathematical Formalism for. In: Meyers, R. (eds) Computational Complexity. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-1800-9_6
[2] Banisch, Sven. "The probabilistic structure of discrete agent-based models." Discontinuity, Nonlinearity, and Complexity 3(3) (2014) 281--292 | DOI:10.5890/DNC.2014.09.005
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[4] Clarke, Edmund M., et al., eds. Handbook of model checking. Vol. 10. Cham: Springer, 2018.
[5] Computer-Aided Formal Verification: 2022-2023, Department of Computer Science Lecturer David Parker https://www.cs.ox.ac.uk/teaching/courses/2022-2023/computeraidedverification/
[6] Macal, Charles M. "Everything you need to know about agent-based modelling and simulation." Journal of Simulation 10, no. 2 (2016): 144-156
[7] Abar, Sameera, Georgios K. Theodoropoulos, Pierre Lemarinier, and Gregory MP O’Hare. "Agent Based Modelling and Simulation tools: A review of the state-of-art software." Computer Science Review 24 (2017): 13-33.