Uncertain lightweight ontologies in a product-based possibility theory framework

作者：Boutouhami Khaoula; Benferhat Salem^*; Khellaf Faiza; Nouioua Farid

来源：International Journal of Approximate Reasoning, 2017, 88: 237-258.

DOI：10.1016/j.ijar.2017.05.012

• Lightweight ontologies
• Possibility theory
• Product-based possibility theory
• Approximate algorithms
• Instance checking

This paper investigates an extension of lightweight ontologies, encoded here in DL-Lite languages, to the product-based possibility theory framework. We first introduce the language (and its associated semantics) used for representing uncertainty in lightweight ontologies. We show that, contrarily to a min-based possibilistic DL-Lite, query answering in a product-based possibility theory is a hard task. We provide equivalent transformations between the problem of computing an inconsistency degree (the key notion in reasoning from a possibilistic DL-Lite knowledge base) and the weighted maximum 2-Horn SAT problem. The last part of the paper provides an encoding of the problem of computing inconsistency degree in product-based possibility DL-Lite as a weighted set cover problem and the use of a greedy algorithm to compute an approximate value of the inconsistency degree. This encoding allows us to provide an approximate algorithm for answering instance checking queries in product-based possibilistic DL-Lite. Experimental studies show the quality of the approximate algorithms for both inconsistency degree computation and instance checking queries.

• 出版日期2017-9