New Polynomial Classes for Logic-Based Abduction

TL;DR

This paper introduces new polynomial classes for propositional logic-based abduction by proposing a general algorithm and analyzing restrictions on knowledge base representations.

Contribution

It presents a general projection-based algorithm and identifies new polynomial classes of abduction problems under specific restrictions.

Findings

New polynomial classes for abduction problems identified.

A general algorithm based on projection is proposed.

Restrictions on knowledge base representations enable polynomial-time solutions.

Abstract

We address the problem of propositional logic-based abduction, i.e., the problem of searching for a best explanation for a given propositional observation according to a given propositional knowledge base. We give a general algorithm, based on the notion of projection; then we study restrictions over the representations of the knowledge base and of the query, and find new polynomial classes of abduction problems.