Describes an empirical study that was conducted to examine the performance of expert search intermediaries from Chemical Abstracts Service. Highlights include subject-independent and subject-dependent expertise; a model of the use of subject-specific knowledge; and implications for computerized intermediary systems and for training human…

Provides overview of Ergonomics Abstracts Retrieval System (EARS), an online bibliographic search and retrieval system in the area of human factors engineering. Other online systems are described, the design of EARS based on inverted file organization is explained, and system expansions including a thesaurus are discussed. (Author/LRW)

Six articles about evaluating information retrieval (IR) systems and methods are briefly described in this introduction to a special issue and some of the major problems that are encountered in evaluating interactive information retrieval are considered. (two references) (LAE)

Presents a theoretical rationale for employing a form of information retrieval algorithm that helps searchers better navigate through large document collections by continually revising probability estimates for document subsets. The algorithm avoids assumptions of index term independence and predicts relevance more accurately with increasing…

Discusses the problems inherent in applying what is learned in a carefully controlled information retrieval (IR) research project to searching the scientific databases available through a large commercial database. STN International is used as an example. (five references) (LAE)

This review of abstracting policies used by database producers focuses on the degree to which these policies incorporate criteria vital for acceptability of abstracts for free-text searching. Each topic in abstracting policy (abstract type, length, content, and language) is examined to consider its effect on retrieval. (MBR)

Current awareness services at AT&T Bell Laboratories are described: bulletins announcing over 80,000 externally published items/year; production of four commercial machine-readable databases and camera-ready bulletin copy by Bell Laboratories Publication, Alerting, and Retrieval System (BELLPAR); photocopy service. Improvements in service are…

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…

Reports algorithm for calculation of term discrimination values that is sufficiently fast in operation to permit use of exact values. Evidence is presented to show that relationship between term discrimination and term frequency is crucially dependent upon type of inter-document similarity measure used for calculation of discrimination values. (13…

Two studies of the cognitive processes involved in online document-based information retrieval were conducted. These studies led to the development of five computational models of online document retrieval which were incorporated into the design of an "intelligent" document-based retrieval system. Both the system and the broader implications of…

Zipfian laws for frequency distributions of word pairs and longer phrases are derived from text sample analysis. From crossing of Zipfian curves, it is deduced that number of multi-word phrases that occur frequently in text is surprisingly small, of same order of magnitude as number of individual word-types. (8 references) (EJS)

Built using a distributed architecture, this prototype distributed information retrieval system uses statistical ranking techniques to provide better service to the end user. Distributed architecture was shown to be a feasible alternative to centralized or CD-ROM information retrieval, and user testing of the ranking methodology showed both…

The U.S. Department of Energy (DOE) software research and development project described explores information seeking behavior of end-user energy experts and develops software offering tutorials on front-end use of DOE/RECON databases and active help in performing online searches. Software development is described and results of prototype testing…

Describes experiment designed to assess information value for individual searchers in realistic search environment. Included in data analysis are comparison of two alternative retrieval methods, evaluation of how well humans are able to estimate document relevance, and investigation of value function components (features and coefficients) and…