300 Chapter 11 Knowledge-IntensIve learnIng: dIet Menu planner
problem features, searching an index structure, or searching in a model of
general domain knowledge. Cases may be retrieved solely from the input
features or from features inferred from the input. Cases that match all input
features are, of course, good candidates for matching, but depending upon
the strategy, cases that match a given fraction of the problem features (input
or inferred) may also be retrieved.
Some tests for relevance of a retrieved case are often executed, par-
ticularly if cases are retrieved based on a subset of features. The matching
process will be easy if the case representation is properly designed. This can
be a problem with indexing vocabular ...