Knowledge in Context: A Strategy for Expert System Maintenance

Knowledge engineering, obtaining knowledge from experts and incorporating it into expert systems is difficult and time consuming. We suggest that these difficulties arise because experts never report on how they reach a decision, rather they justify why the decision is correct. These justifications vary markedly with the context in which they are required, but in context they are accurate and adequate; the difficulties in knowledge engineering arise from taking the justification out of context. We therefore hypothesise that knowledge engineering may be obviated, particularly in the long term maintenance of expert systems, if the rules experts provide are used in the context in which they are given. This paper describes work in progress to test this hypothesis.