Reports an investigation conducted to improve the performance of SDI profiles in a large, complex data base that contains over a million references to scientific and technical literature, and uses full text indexing for retrieval. (Author/MBR)

Introduces the concept of cover coefficient to indexing theory and discusses a way of computing term discrimination values by using the cover coefficient concept, index-term selection, and weight modification. This method is compared to an approach that uses similarity coefficients. (Author/EM)

Describes GRANT, an expert system for finding sources of funding given research proposals. The architecture of GRANT and the implementation of constrained spreading activation (a modified search algorithm based on semantic memory) are described, and recall and precision rates are analyzed. (Author/LRW)

Discusses expert systems and their value as components of information retrieval systems related to semantic inference, and describes IOTA, a model of an intelligent information retrieval system which emphasizes natural language query processing. Experimental results are discussed and current and future developments are highlighted. (Author/LRW)

A Bayesian argument is used to suggest modifications to the Robertson and Jones relevance weighting formula to accommodate the addition to the query of terms taken from the relevant documents identified during the search. (Author)

Reviews the subjective probability estimation literature of six schools of human judgement and decision making: decision theory, behavioral decision theory, psychological decision theory, social judgement theory, information integration theory, and attribution theory. Implications for probabilistic information retrieval are discussed, including…

Describes an expected precision (EP) measure designed to predict document retrieval performance. Highlights include decision theoretic models; precision and recall as measures of system performance; EP graphs; relevance feedback; and computing the retrieval status value of a document for two models, the Binary Independent Model and the Two Poisson…

Identifies characteristics of the experienced online searcher and discusses the results of three searches carried out by a variety of searchers in widely differing subject fields--presence of arsenic in coal, problems of working alone in laboratory or work area, and spectral sensitivity of the insect eye. (8 references) (EJS)

Examines the changing role of controlled vocabulary in the postcoordinate online search, particularly its current role in the formulation of online search strategies. Effects of controlled vocabulary searching on precision and recall and examples of concept "hedges" from the "Thesaurus of ERIC Descriptors" are discussed. Nine…

This paper reports on a transaction log analysis of 51,473 queries from 18,113 users of Excite, a major World Wide Web search engine. Approximately 2,500 of these queries were from the use of relevance feedback. Given the high level of research activity and historical success of relevance feedback in assisting users in locating relevant…

The establishment of a reference filing system, based on optical coincidence retrieval, for an eight-man research group studying gas reactions is described. The complete system is simple to use and gives rapid, precise reference retrieval. (1 reference) (Author)

Introduced are methods for computation of term-term association factors, indexing, assignment of term-document relevance values, and computation for recall and relevance. Recall and relevance are based on quantitative intenal system computations, and results are compared with user evaluations. (Author/MF)

To assess value of abstracts in online information retrieval, this study attempts to match free-text search phrases to index terms and provides classification of documents indicating form of retrieval to be expected by searching three databases--Energyline; Management Contents; and America, History and Life. Results of a sample search are…

Discusses the quality of information retrieval using "free text" searching in full-text databases and presents a critical perspective on the importance of augmenting access to full-text databases through some form of text enhancement, such as the use of a limited controlled vocabulary for indexing general concepts. (Author/JL)

Explores the effects on relevance concerns in traditional online search strategies caused by ranking retrieved documents. Two extreme examples are presented to illustrate the impact of ranking; advantages and limitations of ranking are discussed. (SW)