The substitution information contained in automatically obtained keyword classification is most effectively exploited when: (1) strong similarity connectives only are utilized, (2) grouping is confined to non-frequent terms, (3) term groups are used to provide additional and not alternative descriptive items and (4) descriptor collection frequency…

Empirical significance of document partitions is investigated as a function of index term-weight and similarity thresholds. Results show the same empirically preferred partitions can be detected by two independent strategies: an analysis of cluster-based retrieval analysis and an analysis of regularities in the underlying structure of the document…

Describes research designed to improve automatic pre-coordinate term indexing by applying language analysis techniques to identify term sources in requests, and to generate variant expressions of concepts involved for document text searching. Text analysis, term extraction, variant generation, and retrieval trial are highlighted. Thirteen…

Formal proofs are given of the effectiveness under well-defined conditions of the thesaurus method in information retrieval. It is shown, in particular, that when certain semantically related terms are added to the information queries originally submitted by the user population, a superior retrieval system is obtained in the sense that for every…

Introduced are methods for computation of term-term association factors, indexing, assignment of term-document relevance values, and computation for recall and relevance. Recall and relevance are based on quantitative intenal system computations, and results are compared with user evaluations. (Author/MF)

Describes large scale experiments to test the value of index term weighting based on relevance information, and presents results showing that weighting leads to remarkable improvements in retrieval performance. (Author/CWM)

An evaluation of graph theoretical clusters of index terms which can be extracted from an automatically indexed document collection, and the effects of employing such clusters in automatic document retrieval are described. (19 references) (Author)

Discussion of text analysis and information retrieval and measurement of document similarity focuses on a new text manipulation system called FA (field association)-Sim that is useful for retrieving information in large heterogeneous texts and for recognizing content similarity in text excerpts. Discusses recall and precision, automatic indexing…

Describes a new method for automatic indexing and retrieval called latent semantic indexing (LSI). Problems with matching query words with document words in term-based information retrieval systems are discussed, semantic structure is examined, singular value decomposition (SVD) is explained, and the mathematics underlying the SVD model is…

Explores the concept of information retrieval and summarizes the development of information retrieval systems. The role of relevance judgments as a systems test is discussed, principles of what information systems can and cannot be expected to achieve are presented, and areas of research interest are identified. (43 references) (CLB)

Provides background of automatic indexing and overview of Fully Automatic Syntactically based Indexing of Text (FASIT), a system based on idea that content-bearing words belong to certain syntactic categories. Results of comparison of FASIT with thesaurus and stem-based indexing systems on database of 250 documents and 22 queries are summarized.…

Describes the Belief Function Model for automatic indexing and ranking of documents which is based on a controlled vocabulary and on term frequencies in each document. Belief Function Theory is explained, and the Belief Function Model is compared to the Standard Vector Space Model. (17 references) (LRW)

Summarizes the experimental evidence that indicates that text indexing systems based on the assignment of appropriately weighted single terms produce retrieval results superior to those obtained with more elaborate text representations, and provides baseline single term indexing models with which more elaborate content analysis procedures can be…

Briefly reviews various methodologies for constructing enhanced document representations, discusses their general lack of usefulness, and describes a method of document indexing which uses title words taken from bibliographically related items. Evaluation of this process indicates that it is not sufficiently reliable to warrant incorporation into…

Describes technique for automatic book indexing requiring dictionary of terms with text strings that count as instances of term and text in form suitable for processing by text formatter. Results of experimental application to portion of book text are presented, including measures of precision and recall. Ten references are noted. (EJS)