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Abstract : |
This paper describes the development of a prototype system to generate routing profiles automatically from sets of relevant documents provided by a user, and to assign relevance scores to the documents selected by these profiles. The prototype was developed with the Logicon Message Dissemination System (LMDS) for participation in the Fourth Text REtrieval Conference (TREC-4). Each generated profile contains two sets of terms: a very small set to select documents, and a much larger set to assign a relevance score to each document selected. The profile generator chooses each term and assigns a weight to it, based on its frequency of occurrence in the set of documents provided by the user, and on its frequency of occurrence in a large representative corpus of documents. The LMDS search engine uses the resulting profiles to select documents, and then passes the documents to the scoring prototype for ranking. The score assigned is a function of the weights of all profile terms found in the entire document, and of those found in fixed-length overlapping passages within the document. Performance figures and TREC-4 results are included. An appendix describes a modification to the TREC-4 algorithm, made since the conference, which has produced significant improvements in both recall and precision. 1., |
