- L. Larkey, Margaret E. Connell, Jamie Callan. 2000. Collection selection and results merging with topically organized U.S. patents and TREC data. Abstract: We investigate three issues in d istributed information retrieval, considering both TREC data and U.S. Patents: (1) topical organization o f large text collections, (2) collection ranking and selection with topically organized collections (3) results merging, particularly document score normalization, with topically organized collections. We find that it is better to organize collections topically, and that topical collections can be well ranked using either INQUERY’s CORI algorithm, or the Kullback-Leibler divergence (KL), but KL is far worse than CORI for non-topically organized collections. For r esults merging, collections organized b y topic require global idfs for the best performance. Contrary to results found elsewhere, normalized scores are not as good as global idfs for merging when the collections are topically organized.
