- Tom Ault, Yiming Yang. 2000. kNN at TREC-9. Abstract: We applied a multi-class k-nearest-neighbor based text classiication algorithm to the adap-tive and batch ltering problems in the TREC-9 ltering track. While our systems performed well in the batch ltering tasks, they did not perform as well in the adaptive ltering tasks, in part because we did not have an adequate mechanism for taking advantage of the relevance feedback information provided by the l-tering tasks. Since TREC-9, we have made considerable improvements in our batch ltering results and discovered some serious problems with both the T9P and T9U metrics. In this paper, we discuss these issues and their impact on our ltering results.
