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arXiv · 2410.15081

A Distribution Semantics for Probabilistic Term Rewriting

Germán Vidal
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Abstract

Probabilistic programming is becoming increasingly popular thanks to its ability to specify problems with a certain degree of uncertainty. In this work, we focus on term rewriting, a well-known computational formalism. In particular, we consider systems that combine traditional rewriting rules with probabilities. Then, we define a novel "distribution semantics" for such systems that can be used to model the probability of reducing a term to some value. We also show how to compute a set of "explanations" for a given reduction, which can be used to compute its probability in a more efficient way. Finally, we illustrate our approach with several examples and outline a couple of extensions that may prove useful to improve the expressive power of probabilistic rewrite systems.

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Germán Vidal. 2024-10-19. A Distribution Semantics for Probabilistic Term Rewriting. https://arxiv.org/abs/2410.15081

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