a system for revising probabilis(cid:173)
This paper describes RAPTURE - tic knowledge bases that combines neural and symbolic learning methods. RAPTURE uses a modified version of backpropagation to refine the certainty factors of a MYCIN-style rule base and uses ID3's information gain heuristic to add new rules. Results on re(cid:173) fining two actual expert knowledge bases demonstrate that this combined approach performs better than previous methods.