Bottom-Up Grounding in the Probabilistic Logic Programming System Fusemate
This work addresses a specific bottleneck in probabilistic logic programming systems for researchers and practitioners, representing an incremental improvement.
The paper tackles the challenge of controlling ground clause generation in bottom-up grounding for probabilistic logic programming by introducing a query-guided relevance test that prunes inconsistent rules. The result is competitive or better performance compared to a state-of-the-art system, especially in high branching problems.
This paper introduces the Fusemate probabilistic logic programming system. Fusemate's inference engine comprises a grounding component and a variable elimination method for probabilistic inference. Fusemate differs from most other systems by grounding the program in a bottom-up way instead of the common top-down way. While bottom-up grounding is attractive for a number of reasons, e.g., for dynamically creating distributions of varying support sizes, it makes it harder to control the amount of ground clauses generated. We address this problem by interleaving grounding with a query-guided relevance test which prunes rules whose bodies are inconsistent with the query. We present our method in detail and demonstrate it with examples that involve "time", such as (hidden) Markov models. Our experiments demonstrate competitive or better performance compared to a state-of-the art probabilistic logic programming system, in particular for high branching problems.