Predicate Invention in ILP - an Overview

Inductive Logic Programming (ILP) is a subfield of machine learning dealing with inductive inference in a first order Horn clause framework. A problem in ILP is how to extend the hypotheses language in the case that the vocabulary given initially is insufficient. One way to adapt the vocabulary is to introduce new predicates. In this paper, we give an overview of different approaches to predicate invention in ILP. We discuss theoretical results concerning the introduction of new predicates, and ILP-systems capable of inventing predicates. This work has been supported by the European Community ESPRIT project ILP (Inductive Logic Programming).