Examines the statistical distribution of relevance judgments by reviewing and comparing the results of several studies over the last three decades. A characteristic distribution is examined, and a hypothesis is offered to explain it based on human judging characteristics and the nature of relevance experimentation. (Contains 13 references.) (LRW)

Reports preliminary results of a study that investigated the nature of feedback during 40 uses of user-intermediary-information retrieval system interaction through the use of microanalysis. Types of feedback based on human judgments include magnitude feedback, relevance feedback, term relevance feedback, tactical review feedback, and terminology…

Describes a study that tested the effectiveness of a thesaurus as a search-aid in free text searching of a Finnish full text database. Linguistic and conceptual approaches are discussed; five search modes are explained; recall and precision are examined; and the use of proximity operators is discussed. (Contains 29 references.) (LRW)

Discussion of recall and precision of index terms focuses on an information-theoretic measure of term specificity. Term weighting schemes are described, including the inverse document frequency (IDF) and signal-noise ratio (S/N) approaches; term weighting by specificity is explained; and the need for experiments with test document collections is…

Reports findings of a study conducted at the University of Michigan that replicated an earlier study on users' perceptions of the binary, or dichotomous, nature of their relevance judgments in information retrieval evaluation. Results that support the earlier study are discussed, and further research is suggested. (LRW)

Examines research on the observed values of retrieval effectiveness obtained in searches of files of nearest neighbor document clusters. Results show interdocument similarities used to generate nearest-neighbor clusters are significantly different from randomly generated clusters. (Contains 14 references.) (EAM)

Presents results of simulations that were conducted to test the effects of errors in estimation of individual term probabilities on the performance of a probabilistic information retrieval (PIR) system. Assigning index terms to documents is described; an information retrieval system called Helpnet is explained; and relevance, ranking, and…

Reviews and expands on a 1985 study that described a detailed evaluation of the effectiveness of an operational full-text information retrieval system, STAIRS, which was used by IBM for litigation support. Problems the user faces are described, and recall/precision studies are discussed. (27 references) (LRW)

Discussion of document retrieval systems and measuring system performance focuses on the upper bounds, or maximum performance, that can be obtained with a system. Topics addressed include bounds for retrieval performance; average search length; average precision; incomplete searches; an asymmetric measure of retrieval performance; and measuring…

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…

Discusses the variety of performance measures available for information retrieval systems, search engines, and network filtering agents. Considers how measures of performance at a point in a search can be formally compared, develops criteria related to document orderings, and discusses equivalent ordering and precision and recall. (Author/LRW)

Evaluates the effectiveness of spelling-correction and string-similarity matching methods in retrieving similar words in a Malay dictionary associated with a set of query words. Describes experiments that showed the best search combination used a stemming algorithm, and calculates retrieval effectiveness and relevant means measures from weighted…

Duality is an important topic in informetrics, often less studied in information retrieval where it relates to the unification or symmetry of queries and documents, search formulation versus indexing, and relevant versus retrieved documents. This article examines duality in information retrieval and highlights its connection with hypergeometric…

Discussion of information filtering (IF) and information retrieval focuses on the use of an artificial neural network (ANN) as an alternative method for both IF and term selection and compares its effectiveness to that of traditional methods. Results show that the ANN relevance prediction out-performs the prediction of an IF system. (Author/LRW)

Discusses relevance judgments in information retrieval; considers the collaborative nature of information retrieval in a group, organization, or societal context; and proposes a method that measures relevance based on group/peer consensus. Reports results of an experiment using this method to compare the search performance of different types of…