HUMAN-PERFORMANCE IN FAULT-DIAGNOSIS - CAN EXPERT-SYSTEMS HELP

Two unrelated fields are compared within which fault diagnosis plays a significant role: medical and process control. It is argued that the diagnostic process may be seen to be very similar regardless of the domain of application, and that characteristics of human problem solving are common to all domains, including medicine and process control. However, it is shown that the kind of computer support needed to enhance diagnostic activities varies considerably between these domains. Judgemental biases and application of inappropriate heuristics are shown to be as prevalent among expert diagnosticians in both domains as among non-experts, and the complex concept of diagnosticity is apparently poorly understood. For that reason, medical experts need assistance in generating a wider range of hypotheses than they habitually consider and also in generating probabilistic information to supplement diagnostic performance. By contrast, multilevel displays that emphasize the relationship between critical variables in perceptually salient ways are needed to support process control operators.