A suite of computer programs has been developed for representing the full text of lengthy documents in vector form and classifying them by a clustering method. (Author)

Investigates the presence of clustering structure in a document collection and the influence of the presence of clustering structure on the success of cluster-based retrieval. Term-weight and similarity thresholds are discussed, empirical and statistical significance are considered, and indexing exhaustivity for document representation is…

Describes a clustering algorithm designed for dynamic data bases and presents an update procedure which maintains an effective document classification without reclustering. The effectiveness of the algorithms is demonstrated for a subset of the Cranfield collection. (Author)

Using examples of data from the areas of information retrieval and of multivariate data analysis, six hierarchic clustering algorithms (single link, median, centroid, group average, complete link, Wards's) are examined and evaluated by using three proposed coefficients of hierarchic structure. Nine references are cited. (EJS)

Discusses the problem of processing fuzzy queries in databases and information retrieval systems and presents a prototype of a fuzzy query processing system for databases that is based on data clustering and uses Pascal programing language. Clustering schemes are explained, and the system architecture that uses natural language is described. (14…

Presents system for automatic handling of ordered sets, states based on these sets, and differing points of view regarding Universe of Discourse. Aspects are represented by new logical "overlap" function with examples taken from Ranganathan's horse and carriage parable and several books involving four main concepts (history, geography,…

Describes a method of iterative searching that uses local metrical clustering in the formulation of additional searches by producing searchonyms, terms which are synonymous to keywords in the context of a single query. The method was applied to a database containing Hebrew and Aramaic text. Seven references are listed. (FM)

This issue contains nine articles that provide an overview of trends and research in parallel information retrieval. Topics discussed include network design for text searching; the Connection Machine System; PThomas, an adaptive information retrieval system on the Connection Machine; algorithms for document clustering; and system architecture for…

The single-link cluster method is used to construct a hierarchic classification for the 1400 documents in the Cranfield test collection. A variety of retrieval strategies applied to this hierarchy are evaluated in terms of effectiveness and efficiency. (Author)

Describes the use of relevance feedback to select additional search terms and discusses the extraction of these terms from a maximum spanning tree connecting all terms in the index term vocabulary; retrieval effectiveness for different spanning trees is shown to be similar. Eight references are included. (Author/BK)

Shows how to automatically construct a classification of users and a clustering of documents and cross-references among clusters based on users' information needs. Feedback in the construction of this classification and clustering that allows for the classification to be changed to reflect changing needs of users is also described. (22 references)…

Describes a study conducted on the cystic fibrosis (CF) database, a subset of MEDLINE, that investigated clustering structure and the effectiveness of cluster-based retrieval as a function of the exhaustivity of the uncontrolled subject descriptions. Results are compared to calculations for controlled descriptions based on Medical Subject Headings…

Discussion of relevancy in information retrieval systems focuses on an analysis of the efficiency of various cluster-based retrieval (CBR) strategies. A method for combining CBR and inverted index search is proposed that is cost effective in terms of time efficiency; and results of experiments are reported. (Contains 32 references.) (LRW)

These two articles discuss clustering structure in the Cystic Fibrosis Document Collection, which is derived from the National Library of Medicine's MEDLINE file. The exhaustivity of four subject representations and two citation representations is examined, and descriptor-weight thresholds and similarity thresholds are used to compute…

Reports research results into a methodology for determining similarity between queries characterized by Boolean search request formulations and discusses similarity measures for Boolean combinations of index terms. Rationale behind these measures is outlined, and conditions ensuring their equivalence are identified. Results of an experiment…