Analyzes a study of the effect of controlled variations in indexing vocabulary size on retrieval performance, using the Cranfield 200 and 1400 test collections. Sets of variable-length character strings were tested, in an application of the Cluster Hypothesis and in a series of linear associative retrieval experiments. (Author/SW)

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…

Discusses methods for automatically compiling domain-oriented vocabularies in natural language systems and describes techniques for evaluating the quality of the resulting word lists. A study is described that used subject headings from Grolier's Encyclopedia and the United Press International newswire, and filters for removing high frequency…

Discussion of information retrieval and automatic indexing in digital libraries focuses on Chinese indexing and cross-lingual information retrieval. Investigates the combination and boundary detection approaches based on mutual information for word segmentation, using lexical and statistical information. Reports results of experiments that…

Describes and discusses the findings of an experiment that tested the precision of full-text retrieval enhanced by 29 document term weighting algorithms at the lowest, middle, and highest levels of recall, and compared with the precision of full-text retrieval without algorithms and with paragraph retrieval. (29 references) (Author/CLB)

Identifies current trends in the automation of indexing, of information retrieval, and of interaction between the system and the users. Topics discussed include location, navigation, and indexing; digital libraries; matching documents to queries; weight of concepts; query structure, including fuzzy sets; algorithms; stemming; clustering; users'…

Discusses suffix stripping algorithms used in information retrieval to cluster words derived from a common root under the same stem, and proposes a suffixing algorithm for French which uses grammatical categories to enhance the stemming process. An evaluation of the algorithm is discussed, and an analysis of errors is described. (17 references)…

The emphasis of this text is that the problems of information retrieval are the intellectual ones of subject analysis and description. These problems are not easily solved by technology alone, although certain inroads are being made by knowledge-based expert systems and other computer aids to indexing. Linguistic approaches are also showing…

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…

Discussion of automated indexing techniques focuses on ways to statistically document improvements in the development of an automated keywording system over time. The system developed by the Joint Chiefs of Staff to automate the storage, categorization, and retrieval of information from military exercises is explained, and performance measures are…

Describes the indexing concept of entry terms, and evaluates existing terms in the Medical Subject Headings by comparing them to the results of an automatic indexer. The results of experimental testing of a strategy for creating entry terms using the algorithms of the automatic indexer are presented. (31 references) (CLB)

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…

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…

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…