Robert M. Colomb, Charles Y.C. Chung
A formal equivalence between propositional expert systems and decision tables is proved, and a practicable procedure given to perform the transformation between propositional expert systems and decision tables. The method gave an order of magnitude speed increase for a well-known expert system in routine use. The method is very general: adaptations are shown for forward and backward chaining inferencing engines, inexact reasoning, and systems where some facts have a high cost and must be determined only if necessary. A particular application for the decision table representation is in real-time expert systems, since a simple hardware implementation is available which gives further orders of magnitude increase in performance. Finally, the decision table representation greatly simplifies the problem of completeness and consistency checking.