CHR(PRISM)-based Probabilistic Logic Learning

TL;DR

This paper introduces CHRiSM, a new probabilistic logic formalism combining CHR and PRISM, enabling high-level modeling and inference for complex statistical models with probabilistic rules.

Contribution

It defines the syntax, semantics, and implementation of CHRiSM, a novel language integrating CHR and PRISM for probabilistic logic programming.

Findings

Defined the syntax and semantics of CHRiSM

Implemented a CHRiSM system based on CHR(PRISM)

Demonstrated potential applications in probabilistic modeling

Abstract

PRISM is an extension of Prolog with probabilistic predicates and built-in support for expectation-maximization learning. Constraint Handling Rules (CHR) is a high-level programming language based on multi-headed multiset rewrite rules. In this paper, we introduce a new probabilistic logic formalism, called CHRiSM, based on a combination of CHR and PRISM. It can be used for high-level rapid prototyping of complex statistical models by means of "chance rules". The underlying PRISM system can then be used for several probabilistic inference tasks, including probability computation and parameter learning. We define the CHRiSM language in terms of syntax and operational semantics, and illustrate it with examples. We define the notion of ambiguous programs and define a distribution semantics for unambiguous programs. Next, we describe an implementation of CHRiSM, based on CHR(PRISM). We discuss the relation between CHRiSM and other probabilistic logic programming languages, in particular PCHR. Finally we identify potential application domains.