title: An analysis of statistical term strength and its use in the indexing and retrieval of molecular biology texts.
abstract: The biological literature presents a difficult challenge to information processing in its complexity, diversity, and in its sheer volume. Much of the diversity resides in its technical terminology, which has also become voluminous. In an effort to deal more effectively with this large vocabulary and improve information processing, a method of focus has been developed which allows one to classify terms based on a measure of their importance in describing the content of the documents in which they occur. The measurement is called the strength of a term and is a measure of how strongly the term's occurrences correlate with the subjects of documents in the database. If term occurrences are random then there will be no correlation and the strength will be zero, but if for any subject, the term is either always present or never present its strength will be one. We give here a new, information theoretical interpretation of term strength, review some of its uses in focusing the processing of documents for information retrieval and describe new results obtained in document categorization.
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
authors.forename: W J
authors.initials: WJ
authors.lastname: Wilbur
authors.forename: Y
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000043:Abstracting and Indexing; D000465:Algorithms; D001499:Bayes Theorem; D015982:Bias; D006801:Humans; D016247:Information Storage and Retrieval; D016018:Least-Squares Analysis; D016239:MEDLINE; D008967:Molecular Biology; D015203:Reproducibility of Results; D013358:Subject Headings