Report Number: CS-TR-82-923
Institution: Stanford University, Department of Computer Science
Title: Explanatory power for medical expert systems: studies in the
representation of causal relationships for clinical
Author: Wallis, Jerold W.
Author: Shortliffe, Edward H.
Date: July 1982
Abstract: This paper reports on experiments designed to identify and
implement mechanisms for enhancing the explanation
capabilities of reasoning programs for medical consultation.
The goals of an explanation system are discussed, as is the
additional knowledge needed to meet these goals in a medical
domain. We have focussed on the generation of explanations
that are appropriate for different types of system users.
This task requires a knowledge of what is complex and what is
important; it is further strengthened by a classification of
the associations or causal mechanisms inherent in the
inference rules. A causal representation can also be used to
aid in refining a comprehensive knowledge base so that the
reasoning and explanations are more adequate. We describe a
prototype system which reasons from causal inference rules
and generates explanations that are appropriate for the user.