Bayesian network semantics for Petri nets

Recent work by the authors equips Petri occurrence nets (PN) with probability distributions which fully replace nondeterminism. To avoid the so-called confusion problem, the construction imposes additional causal dependencies which restrict choices within certain subnets called structural branching cells (s-cells). Bayesian nets (BN) are usually structured as partial orders where nodes define conditional probability distributions. In the paper, we unify the two structures in terms of Symmetric Monoidal Categories (SMC), so that we can apply to PN ordinary analysis techniques developed for BN. Interestingly, it turns out that PN which cannot be SMC-decomposed are exactly s-cells. This result confirms the importance for Petri nets of both SMC and s-cells.

Authors

• Roberto Bruni
• Hernán Melgratti
• Ugo Montanari

Keywords

• Bayesian nets
• Petri nets
• Conditional probability distributions
• Confusion
• Branching cells
• Kleisli categories
• Symmetric monoidal categories
• Forward and backward inference