Partial Orders and Indifference Relations: Being
Purposefully Vague in Case-Based Retrieval*

Alex Ferguson and Derek Bridge

Department of Computer Science, University College, Cork
{a.ferguson, d.bridge}@cs.ucc.ie



Abstract. In this paper, we look at case retrieval systems for product 
selection. Such systems are interactive. This places demands on the
technology: customers must be able to specify their requirements in ways
that are meaningful to them; and, the cases that are retrieved must be
comprehensible in terms of the customer requirements. To meet these
demands, we introduce to case retrieval the notions of similarity metrics
with partially-ordered return types and of relations that express indifference 
between degrees of similarity.
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