In this paper, we propose a syntax-based text retrieval system for on-line language learning and use a fast regular expression search engine as its main component. Regular expression searches provide more scalable querying and search results than keyword-based searches. However, without a well-designed index scheme, the execution time of regular…

An evaluation of the Epilepsy Abstracts Retrieval System (EARS) was performed. Searches were conducted on the on-line system and evaluated in terms of recall, precision, and general user satisfaction. A detailed analysis of factors affecting the success and failure of the on-line searches was carried out. (4 references) (Author/SJ)

Experience of browsing with a text retrieval system is reported. The technique discussed consists of adding and deleting query terms on successive interactive cycles. The number of hits consistently increased, while the number of false drops consistently decreased on successive cycles. The search system used allows non-Boolean free form query…

The purpose of the investigation was to determine how effectively biomedical practitioners, with a minimum of introduction to the system, can conduct on-line searches to satisfy their own information needs. The searches were conducted on the Abridged Index Medicus data base as implemented on the on-line ELHILL system (AIM-TWX). ELHILL is the ORBIT…

The Hepatitis Knowledge Base (text of prototype information system) was used for modifying and testing "A Navigator of Natural Language Organized (Textual) Data" (ANNOD), a retrieval system which combines probabilistic, linguistic, and empirical means to rank individual paragraphs of full text for similarity to natural language queries…

Presents information retrieval design approach in which queries of computer-based system consist of sets of terms, either unweighted or weighted with subjective term precision estimates, and retrieval outputs ranked by probability of usefulness estimated by "maximum entropy principle." Boolean and weighted request systems are discussed.…

Describes an experiment in passage retrieval for scientists using a variety of forms of retrieval question and search words selected independently by two different people. (FM)

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…

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.…

Retrieval performance of the iso-content-based angle similarity measure within the angle, distance, conjunction, disjunction, and ellipse retrieval models is compared with retrieval performance of the distance similarity measure and the angle similarity measure. Results show the iso-content-based angle similarity measure achieves satisfactory…

The periodic TRECs (Text Retrieval Conferences) have reported the results of a variety of recall studies in large-scale document retrieval. While the efforts of TREC are noteworthy and laudable, there are reasons why its results, especially the recall values that are central to its conclusions, should be accepted with some caution. (Contains 17…

Presents an interaction model and an experimental method for information retrieval. This automated method helps identify which user and system variables are relevant, which are independent of other variables, and which ranges of the variables are most important. Results show that relevance feedback consistently improves retrieval performance. (AEF)

Describes the Canadian On Line Enquiry (CAN/OLE) system. (PF)

This paper reviews studies of information dissemination as a basis for determining how on-line retrieval can best compete with a multitude of other sources of references. (22 references) (Author/SJ)

Describes the STATUS information retrieval system, which is a free text, Boolean-type system, concentrating on recent developments and improvements. The use of pre- and postprocessors is discussed, and how STATUS can be integrated into existing information systems is illustrated. An appendix lists selected users and applications. (Author/JD)