A comparative evaluation of results in terms of recall and precision from queries submitted to systems with automatic and manual subject indexing. Differences were attributed to query formulation. The effectiveness of automatic indexing was found equivalent to manual indexing. (Author/KP)

Outlines the concepts and facilities of SLC-II, a basic support for R&D in automatic documentation and language translation, and gives a detailed description of its use in automatic indexing. The design and running of a full-scale pilot project is described, with a parallel experiment in the effectiveness of "thesaurus enrichment" by semiautomatic…

Reports a study that examined 10 collections of mainly scientific subject areas indexed using Farradane's system of relational indexing. It compared (1) the use of relations, (2) the use of concept types, (3) the cross sections (or shape) of abstracts, and (4) the properties of "nodes." Statistical tables and graphs are included.…

Describes the two basic approaches to the calculation of term discrimination values for automatic indexing. The results of an experiment that investigated the differences between algorithms of these two approaches in terms of their impact on the discrimination value model are reported and discussed. (13 references) (Author/CLB)

Describes experiments that compared a new method for automatically analyzing semantic structures in text by statistical means with the standard vector space model. Findings indicate that combining both methods improved performance over either alone. The effects of other experimental variables on retrieval performance (term weighting, suffix…

Describes an investigation of the use of document components, such as terms, sentences, and whole documents, for indexing and retrieval. A number of probabilistic similarity measures based on document components are studied, as well as a new method of handling probability estimations involving small sample sizes. (24 references) (Author/CLB)

Demonstrates efficiency of preparation of query description using semantic analyser method based on analysis of semantic structure of documents in field of automatic indexing. Results obtained are compared with automatic indexing results performed by traditional methods and results of indexing done by human indexers. Sample terms and codes are…

Describes three models for probabilistic indexing, all based on the Darmstadt automatic indexing approach, and presents experimental evaluation results for each. The discussion covers the improved retrieval effectiveness of probabilistic indexing over binary indexing, and suggestions for using this automatic indexing method with free text terms.…

Describes study that compared and judged the quality of subject indexing in online bibliographic databases. Documents from medical behavioral science literature are used with terms drawn from MEDLINE, PsychINFO, BIOSIS, and Excerpta Medica. Comparative statistics are presented on how each database links related documents and discriminates among…

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…

Describes study that compared terminology indexing and citation indexing to determine the similarity of documents retrieved. Information science articles from 1971 to 1983 in three journals were studied for term co-occurrences. The distinction between relevant and pertinent documents is discussed, and further research topics are suggested. (LRW)

Assesses the impact of current coverage and indexing policies on MEDLINE's retrieval performance in the medical behavioral sciences literature by comparing retrievals in EXCERPTA MEDICA, PSYCHINFO, SCISEARCH, and SOCIAL SCISEARCH. Searches were made with descriptors, cited references, and natural language, and recall, precision, and novelty ratios…

These two articles discuss clustering structure in the Cystic Fibrosis Document Collection, which is derived from the National Library of Medicine's MEDLINE file. The exhaustivity of four subject representations and two citation representations is examined, and descriptor-weight thresholds and similarity thresholds are used to compute…

Examines the use of various statistical techniques for generating domain-oriented multiword vocabulary terms for natural language database systems. Conclusions show the vocabulary clustering effect should be considered when making significance calculations and that a simple ratio of subject matter relative frequency to total sample relative…

This second report on a two-part study on the application of informetrics to information retrieval (IR) system design used models of database contents in a factorial simulation study at the University of Western Ontario. The study explored whether different file structures were better suited for different informetric environments. (32 references)…