“…Specifically, PDQ's MAP performance is .31, .24, .21, and .18 for TREC'99, TREC'00, TREC'01, and TREC'02, respectively, while that of PDQ∧NEQ is .33, .26, .23, and .21. This finding, which echoes those from work on using named entities for improving passage retrieval performance for QA [3,5,1], attests to the effectiveness, in terms of retrieval performance, of our entity-based judge.…”