MODELING IN THE DESIGN OF A KBS VALIDATION SYSTEM

We describe and illustrate the modeling issues in the design of a system for validation of knowledge based systems (KBSs). The domain of such a validation system is "KBSs and their validation problems.' The basic idea in our solution is the following. Since different KBSs may use different knowledge representation languages, we first represent the target KBS (i.e., the KBS to be validated) in a general formal model of KBS, and then validate it in this form. The advantage of this strategy is that validation problem solving needs only to refer to the common language of the general formal model. We present a set of possible conceptual abstraction levels in such a model, and argue that each level is associated with a related view on validation problems. Since high level characterizations are difficult to abstract from current knowledge representation languages, we consider the formal aspects of modeling mainly at the "lowest" level, the so-called inference primitive level. We illustrate the approach by formalizing a solution for selected modeling issues at this level.