Explanation-based Similarity:
A Unifying Approach for Integrating Domain
Knowledge into Case-based Reasoning for
Diagnosis and Planning Tasks

Ralph Bergmann, Gerd Pews, Wolfgang Wilke

University of Kaiserslautern
Dept. of Computer Science
P.O. Box 3049
67653 Kaiserslautern, Germany
E-Mail: {bergmann,pews,wilke}@informatik.uni-kl.de


Abstract. Case-based problem solving can be significantly improved
by applying domain knowledge (in opposition to problem solving knowledge), 
which can be acquired with reasonable effort, to derive explanations 
of the correctness of a case. Such explanations, constructed on
several levels of abstraction, can be employed as the basis for similarity
assessment as well as for adaptation by solution refinement. The general
approach for explanation-based similarity can be applied to different real
world problem solving tasks such as diagnosis and planning in technical
areas. This paper presents the general idea as well as the two specific,
completely implemented realizations for a diagnosis and a planning task.
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