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)

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.…

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)

A comparison of the effectiveness of information retrieval based on full-text documents with retrieval based on paragraphs, abstracts, or controlled vocabularies was accomplished using a subset of journal articles with nine search questions. It was found that full-text retrieval achieved significantly higher recall and lower precision than did the…

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…

Presents criteria for an effective syntagmatic relator system and describes how conceptual syntagmatic relationships are expressed in natural language, commenting on the adequacy of such expressions for document retrieval systems. Only one type of expression, a gestalt structure, represented as a frame, conforms to the criteria. (Author/JKP)

Describes SAPHIRE, an experimental information retrieval system featuring concept-based automated indexing, natural language input, and relevance-based retrieval; and compares its retrieval effectiveness with other indexing approaches in a Boolean-based searching environment. Indexing in MEDLINE is described, and a test collection of AIDS…

Describes a study of the retrieval results of World Wide Web search engines. Research quantified accurate matches versus matches of arguable quality for 200 subjects relevant to undergraduate curricula. Both "evaluative" engines (Magellan, Point Communications) and "nonevaluative" engines (Lycos, InfoSeek, AltaVista) were…

Presents the human evaluation of ILIAD, a program for machine-aided indexing that was designed to assist expert librarians in computer-aided indexing and document analysis. Topics include controlled indexing and free indexing; natural language and concept-based information retrieval; evaluation methodology; syntactic variations; and a comparison…

Investigated the impact of term frequencies, term distributions, and indexing exhaustivity on the representation of document spaces in a visual, vector-based retrieval environment. Compares document-space densities and discusses visualization techniques, term weights, and implications for automatic indexing in information retrieval systems.…

Describes an experiment comparing the performance of an automatic full-text indexing software for personal computers (i.e., the Quick-Finder facility in WordPerfect 6.1 for Windows) with the human intellectual assignment of indexing terms to each document in a collection. Results are discussed in terms of ease of use, the time factor, and recall…

Compares the user features of an in-house online search system based on automatic indexing with those of commercial search services, considering specific user types, file structure and applications, and the basic operating system environment. (FM)

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…

Describes a study that compared two information retrieval systems on a full-text medical database: one featured concept-based automatic indexing and statistical retrieval techniques, and the second used traditional word-based Boolean techniques. Evaluation of search results by calculating relative recall and precision is discussed, and user…