USING COMPUTATION TREE LOGIC FOR INTELLIGENT INFORMATION SEARCH ON THE WEB

Web engines crawl hyperlinks to search for new documents; yet when they index discovered documents they basically revert to conventional information retrieval models and concentrate on the indexing of terms in a single document. We propose to overcome such limits with an approach based on temporal logic. By modeling a web site as a finite state transition system we are able to define complex and selective queries over hyperlinks with the aid of Computation Tree Logic operators. We deployed the proposed approach in a prototype system that allows users pose queries in natural language. Queries are automatically translated in Computation Tree Logic, and the answer returned by our system is a set of paths. Experiments carried out with the aid of human experts show improved retrieval effectiveness with respect to current search engines.