A model for an information retrieval system in which recall and precision are inversely related is described, and then the anomaly is resolved. (PF)

Discussion of document ranking methods to calculate the conceptual distance between a Boolean query and a document focuses on the Knowledge-Based Extension Boolean Model which evaluates weighted queries and documents effectively and avoids problems of previous methods. Semantic networks are discussed, and is-a hierarchies are explained. (21…

Discusses term weighting formulae and their use for selecting new terms to enhance a search statement and for weighting the terms for retrieval purposes once selected. The Swets model of information retrieval system performance is described, an approach to term selection is presented, and future research is suggested. (five references) (LRW)

Reports on a theoretical model of structured document indexing and retrieval based on the Dempster-Shafer Theory of Evidence. Highlights include passage retrieval, hypertext, relevance, information needs, implementation of the model, an evaluation scheme designed to test the model's effectiveness, and results of experiments that investigated…

Reports experiments with a term weighting model incorporating relevance information in which it is assumed that index terms are distributed dependently. It is argued that, if high recall searches are required, relevance feedback based on the modified dependence model may be superior to the Boolean search. (Author/VT)

Reports on two experiments investigating the relationship between topical subject expertise and the assessment of relevance. Results indicate that topical subject expertise enhances effects of the semantic distance model (SDM), and that relevance assessment is a contingent, psychological phenomenon that is part of the human-perception task of…

Examines fashioning of model for surrogate to facilitate user selection of appropriate film or video work for particular use. A matrix of time line and film or video document characteristics is proposed as primary aspect of surrogate graphic record, raising issues of description and sampling within abstracting process. (47 references) (EJS)

Discussion of information retrieval focuses on an Interaction Information Retrieval model in which documents are interconnected; queries and documents are treated in the same way; and retrieval is the result of the interconnection between query and documents. A theoretical mathematical formulation of this type of retrieval is given. (Contains 31…

Reviews the progress of parallel computing in information retrieval (IR) and stresses the importance of the motivation in using parallel computing for text retrieval. Analyzes parallel IR systems using a classification defined by Rasmussen; describes retrieval models used in parallel information processing; and suggests areas of needed research.…

Discusses thesauri as tools for multilingual information retrieval and cross-cultural communication. Considers the need for multilingual thesauri and the importance of explicit conceptual structures, and introduces a pilot thesaurus, InfoDEFT (Information Deutsch-English-Francais Thesaurus), as a possible model for new online thesauri which are…

Explores the role of paradigms in information retrieval research and discusses the nature of a paradigm and the applicability of the paradigm concept to a multidisciplinary field such as information science. The features of the physical paradigm and the cognitive paradigm are outlined, and their origins, nature, and role are examined. (55…

Examines the main mathematical approaches to information retrieval, including both algebraic and probabilistic models, and describes difficulties which impede formalization of information retrieval processes. A number of developments are covered where new theoretical understandings have directly led to improved retrieval techniques and operations.…

Two statistical models for estimating search time have been developed for the CA Condensates data base using the University of Georgia Text Search System. Comparative timings between the Chemical Abstracts Service search program and the University of Georgia search program are made for the Ca Condensates data base. (5 references) (Author/NH)

Explicates a definition and theory of "aboutness" and aboutness analysis developed by text linguist van Dijk; explores implications of text linguistics for bibliographic classification theory; suggests the elements that a theory of the cognitive process of classifying documents needs to encompass; and delineates how people identify…

Introduces some of the considerations behind the teaching of research methodology at the Royal School of Library and Information Science (Denmark) at the masters level. Discusses information retrieval experiments; sampling problems; the concept of a model; and statistical analysis and its role in information retrieval experiments. (Contains 25…