On Quality Measures for Case Base Maintenance

Thomas Reinartz1, Ioannis Iglezakis1, and Thomas Roth-Berghofer2

1 DaimlerChrysler AG, Research & Technology, FT3/AD,
P.O. Box 2360, 89013 Ulm, Germany
{ioannis.iglezakis,thomas.reinartz}@daimlerchrysler.com
2 tec:inno GmbH,
Sauerwiesen 2, 67661 Kaiserslautern, Germany
thomas.rothberghofer@tecinno.com




Abstract. Case base maintenance is one of the most important issues
for current research in CaseBased Reasoning (CBR). In this paper, we
outline two novel steps as part of the maintenance phase of the CBR process. 
The review step covers assessment and monitoring of the knowledge
containers whereas the restore step actually modifies the contents of the
containers according to recommendations resulting from the review step.
Here, we focus our attention on the review step for the case base. For
this purpose, we define several quality measures based on different case
and case base properties that describe specific characteristics of the case
base such as correctness, consistency, uniqueness, minimality and incoherence. 
These measures allow an initial implementation of the review
step for the case base container. We conclude the paper with an outline
of future work to extend these aspects of maintenance in CBR.
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