Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

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To validate the quality of our categorization, the next section discusses series of experiments that compare the performance of the vector space categorization approach with one of the top classifiers, Naïve-Bayes (Friedman et al., 1997).
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