How to Discover a Knowledge Representation for Causal Reasoning by Studying an Expert Physician

The ability to identify and represent the knowledge that a human expert has about a particular domain is a key method in the creation of expert computer system. The first part of this paper demonstrates a methodology for collecting and analysing observations of experts at work, in order to find the conceptual framework used for the particular domain. The second part develops a representation for qualitative knowledge of the structure and behavior of a mechanism. The qualitative simulation, or envisionment, process is given a qualitative structural description of a mechanism and some initialization information, and produces a detailed description of the mechanism's behavior. This "vertical" slice of the construction of a cognitive model demonstrator, an effective knowledge acquisition method for the purpose of determining the structure of the representation itself, not simply the content of the knowledge to be encoded in that representation. Most importantly, it demonstrates the interaction among constraints derived from the textbook knowledge of the domain, from observations of the human expert, and from the computational requirements of successful performance.