REVEALING THE STRUCTURE OF RULE-BASED SYSTEMS

A structural model for rule-based systems, where the structural compon ents of the rule base are modeled as rule base execution paths, plays an important role in the life-cycle of a rule-based system. Although a number of attempts have been made in the literature to formalize the structure of a rule base using the notion of a rule base execution pat h, none of these is entirely adequate: previous attempts suffer from a mbiguity, can be computationally intractable, and do not accurately ca pture the intent of the rule base designer. This paper reports a new m odel for a rule base execution path, incorporating a notion for the st ructure of the problem to be solved by the rule-based system, permitti ng the model to overcome the limitations of previous approaches. This model for the paths in a rule base has been embodied in a rule base an alysis tool called Path Hunter. Path Hunter is used to analyze a rule base consisting of 442 CLIPS rules. In this analysis, we show how the computational tractability of searching for paths can be controlled by the rule base designer.