Closed world specialisation inside the induction process

Article type: Research Article

Authors: Drole, Miha^* | Kononenko, Igor

Affiliations: Faculty of Computer and Information Science, University of Ljubljana, Večna pot, Ljubljana, Slovenia

Correspondence: [*] Corresponding author: Miha Drole, Faculty of Computer and Information Science, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia. E-mail:[email protected]

Abstract: This paper explores the idea of closed world specialisation (CWS). While traditional CWS is performed as a postprocessing step, we propose two different approaches to incorporating it into the induction process of a bottom-up inductive logic programming system. The motivation comes from the fact that using CWS as a postprocessing step is incapable of solving problems in which the negated part of the hypothesis is crucial. We apply the proposed approaches to the ProGolem bottom-up ILP system. We give examples of problems, where classical CWS fails to find a complete and consistent solution, whereas the proposed approaches succeed. Tests on real-world datasets show that the proposed approaches perform at least as well as regular CWS, while being better in terms of predictive accuracy in some cases. We also point out some weaknesses of different CWS approaches.

Keywords: Negation, bottom-up inductive logic programming, nonmonotonic inductive logic programming

DOI: 10.3233/IDA-160830

Journal: Intelligent Data Analysis, vol. 20, no. 4, pp. 745-765, 2016