Using type inference and induced rules to provide intensional answers

A new approach is presented that uses knowledge induction and type inference to provide intensional answers. Machine learning techniques are used to analyze database contents and to induce a set of if-then rules. Type inference which is based on forward inference and backward inference is developed that uses database type hierarchies to derive the intensional answers for a query. It is shown that more precise intensional answers can be derived by properly merging the type inference results from multiple type hierarchies. A prototype intensional query-processing system which uses the proposed approach has been implemented. Using a ship database as a testbed, the effectiveness of the use of type interference and induced rules to derive specific intensional answers is demonstrated