Case Memory and Retrieval Based on the Immune
System

John E. Hunt, Denise E. Cooke and Horst Holstein
Centre for Intelligent Systems, Department of Computer Science,
University of Wales, Aberystwyth,
Penglais Campus, Aberystwyth, Dyfed,
SY23 3DB United Kingdom,
Email: {jjh,dzc,hoh} @uk.ac.aber
Tel: [ +44] (0)1970 622537

June 27, 1995

Abstract
	A variety of case memory organisations and case retrieval techniques have been
proposed in the literature. Each of these has different features which can affect how useful
they are for different applications. However, in applications which are likely to hold very
large numbers of cases. which are highly volatile. and the structure of which is poorly
understood, most of the current approaches are unsuitable.
	In this paper we present a novel approach to case memory organisation and case
retrieval based on metaphors taken from the human immune system. We illustrate how the
immune system is inherently case based and how it relies on its content addressable
memory, and a general pattern matcher, to help it identify new antigens (new situations)
which are similar to old antigens (past cases). We construct a case memory based on the
immune system theory and show how its pattern recognition. learning and memory
operations can support CBR.
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