Towards a Conceptual Framework for Expert System Validation

In this paper we address a number of fundamental questions around validation of expert systems (ESs), an emerging field that still lacks of a comprehensive treatment in the literature. The final aim is to get a conceptual framework for ES validation, what is a difficult task because of the immaturity of the field. We analyze ES validation from four points of view. First, we consider the meaning of validation in ESs, what raises some terminological questions. We propose precise definitions for the terms verification, validation, evaluation and testing, that are in compliance with their respective meanings in software engineering. Second, we consider a number of validation targets, the elements or processes on which some validation activity can be made. Third, we discuss briefly specific techniques to achieve an effective validation for these targets. And fourth, we locate these validation targets in an ES life-cycle.