Report Number: CS-TR-82-908
Institution: Stanford University, Department of Computer Science
Title: Neomycin: reconfiguring a rule-based expert system for application to teaching
Author: Clancey, William J.
Author: Letsinger, Reed
Date: May 1982
Abstract: NEOMYClN is a medical consultation system in which MYClN's knowledge base is reorganized and extended for use in GUIDON, a teaching program. The new system constitutes a psychological model for doing diagnosis designed to provide a basis for interpreting student behavior and teaching diagnostic strategy. The model separates out kinds of knowledge that are procedurally embedded in MYClN's rules and so inaccessible to the teaching program. The key idea is to represent explicitly and separately a domain-independent diagnostic strategy in the form of meta-rules, knowledge about the structure of the problem space, causal and data/hypothesis rules and world facts. As a psychological model, NEOMYCIN captures the forward-directed, "compiled associations" mode of reasoning that characterizes expert behavior. Collection and interpretation of data are focused by the "differential" or working memory of hypotheses. Moreover, the knowledge base is broadened so that GUIDON can teach a student when to consider a specific infectious dlsease and what competing hypotheses to consider, essentially the knowledge a human would need in order to use the MYCIN consultation system properly.