CDW weights locally by class level groupings. Thus it should perform well in
domains with homogeneous classes that are distinguished by dierent features
particular to each class. The same approach can be applied to compute weights
for groups more nely or coarsely grained than individual classes. For example,
if a particular class was dened by the disjunction of two distinct subconcepts,
then one might wish to compute dierent weights for the two sets of instances
belonging to each subconcept. Unfortunately, subclass groupings are generally
not known a priori, and computing appropriate groupings is not a straightfor- ward problem. Because of these diculties, we have not pursued this particular
approach further. Instead, we examined three variants of the CDW algorithm:
one that eliminates locality by using global weights derived from the local CDW
weights, another that uses ner-grained locality by associating dierent weights
with each individual feature value, and a third that is a straightforward combination
of the rst two
CDW weights locally by class level groupings. Thus it should perform well indomains with homogeneous classes that are distinguished by di erent featuresparticular to each class. The same approach can be applied to compute weightsfor groups more nely or coarsely grained than individual classes. For example,if a particular class was de ned by the disjunction of two distinct subconcepts,then one might wish to compute di erent weights for the two sets of instancesbelonging to each subconcept. Unfortunately, subclass groupings are generallynot known a priori, and computing appropriate groupings is not a straightfor- ward problem. Because of these diculties, we have not pursued this particularapproach further. Instead, we examined three variants of the CDW algorithm:one that eliminates locality by using global weights derived from the local CDWweights, another that uses ner-grained locality by associating di erent weightswith each individual feature value, and a third that is a straightforward combinationof the rst two
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