A single issue of Nuclear Science Abstracts, containing about 2,300 abstracts, was indexed by Universal Decimal Classification (UDC) using the Special Subject Edition of UDC for Nuclear Science and Technology. The descriptive cataloging and UDC-indexing records formed a computer-stored data base. A systematic random sample of 500 additional…

Describes various modifications of query formulations, or moves, made by experienced online searchers to improve search results. Operational moves that modify query formulation while keeping meaning of query components unchanged and conceptual moves that change meaning of query components are described; all moves are then related to search tactics…

Describes probabilistic document retrieval systems as a sequential learning process, in which the system learns the parameters of probability distributions describing the frequencies of feature occurrences in relevant and nonrelevant documents. Several techniques for estimating the parameters of distributions are described and the results of tests…

Discusses indeterminancy of selection of terms by indexers and by inquirers as major factors influencing subject access to documents in document retrieval systems. Five types of interactions between these two indeterminancies are discussed, and a change in traditional method of subject searching is suggested to reduce effect of inter-indexer…

Discussion of database design that allows wider range of capabilities than conventional information retrieval database covers prestructuring of searches to pinpoint target items, which are selected from browseable display, and navigation capability, which allows user to move from record to record within database to facilitate extraction of…

Relative effectiveness of indexing using full-text or less than full-text was tested using non-Boolean, chaining type of file structure and searching method. Indexing was done using titles, abstracts, full-text, references, and various combinations; Goffman's indirect method of information retrieval was used to structure and search file.…

Online seaches of sample topics in the area of forensic medicine were conducted in the following life science databases: Biosis Previews, Excerpta Medica, Medline, Scisearch, and Chemical Abstracts Search. Search outputs analyzed according to criteria of recall, uniqueness, overlap, and utility reveal the need for a cross-database approach to…

With the number and types of documents in digital library systems increasing, tools for automatically organizing and presenting the content have to be found. While many approaches focus on topic-based organization and structuring, hardly any system incorporates automatic structural analysis and representation. Yet, genre information…

Five models which perform search tasks of the Data Base Access and Search Environment (DBASE) are presented and used for comparison with subject search performance--unconstrained (rule-based, decision theoretic) and constrained (optimal rule-based, rule-based, probabilistic rule-based). Previous experiments and the modeling approach are briefly…

Reviews 12 different methods of information retrieval for the reduction of a large set by removal of irrelevant or unwanted elements, including logic revision (use of "and" and "not" logic, classification codes, limit commands, field restriction), concept revision, and terminology revision. Examples for each option are given.…

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.…

This description of the implementation of online search services in a small college library focuses on the low-cost, time-conscious methods adopted for searching, publicity, the policy for determining search fees, and evaluation. Sample materials provided include a poster, online statistics, a questionnaire, and a printout. (RBF)

Describes a technique for automatic reformulation of Boolean queries which compares favorably with feedback as employed in a SMART system. Using patron relevance judgments, prevalence measures reflecting term distribution in relevant and nonrelevant documents are derived to guide the construction of a Boolean query for a subsequent retrieval.…

Analyzes the use of weights to denote a query representation and/or the indexing of a document as a generalization of a Boolean retrieval system. Criteria are given for the functions used to evaluate the relevance of the records to a specific query and a new evaluation approach is suggested. (CWM)

Presents a new method of document retrieval based on the fundamental operations of fuzzy set theory. Basic notions are introduced. Then the syntax and semantics of the proposed language for document retrieval is given, and an algorithm allocating documents to particular queries is described and its properties are discussed. (Author/CWM)