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…

Proposes and explains a new mechanism for controlling the access requests in information protection systems that is based on Newton's interpolating polynomial. Access control matrices are discussed; single-key-lock systems are described; relevant algorithms are explained; and an example of the new mechanism is included. (10 references) (LRW)

Views information as residual or catalytic form of energy which regulates other forms of energy in natural and artificial systems. Parallel human information processing (production systems, algorithms, heuristics) and information measurement are discussed. Suggestions for future research in area of parallel information processing include a matrix…

Describes the theoretical framework of a retrieval system that uses data structures called bitmaps to improve search algorithms for medium-sized systems. Information retrieval systems that contain the full text of the documents are discussed, and the use of inverted files such as concordances for small texts is explained. (24 references) (LRW)

Describes fast, dynamic update algorithms for document retrieval systems. B-trees are discussed; the M-B-T file directory structure is explained; insertions and deletions in inverted files are described; and performance evaluation is discussed. An appendix provides the formal definition of an M-B-T directory. (Contains 18 references.) (LRW)

Presents a modification function for weights of descriptors for documents in fuzzy retrieval systems which includes some desirable properties that are lacking in the model proposed by Choros and Danilowicz in their study on relative indexing. (MBR)

Discusses properties of multiple attribute tree (MAT) and inverted file structures; establishes suitability of MAT data structure for bibliographic files using worst-case performance measures; provides arguments to establish MAT average case superiority; and proposes an efficient adaptation of MAT data structure to exploit special features of MAT…

Describes methods for effecting the partition of information systems consisting of many components and interconnections into subsystems which are later made to interface with one another achieving an overall system. Clustering algorithms for the specific case of information systems are obtained and exemplified. Twenty-seven references are…

An information retrieval system which aspires to retrieval of relevant documents should have second stage which will order topical set to provide maximum informativeness to requestor. A two-stage system concerned only with topicality can be iterated to generate a high recall set and discard imprecise documents without user input. (EJS)

Discusses end-user searching in Boolean information retrieval systems considers the role of search intermediaries and proposes a model of user preferences that incorporates a user's profile. Highlights include document representation; information queries; document output ranking; calculating user profiles; and selecting documents for a local…

Offers characterization of sign-transmission which is more general than conventional signal-transmission theory. Concepts and terminology, formal description of individual communications process, reconciliation with classical signal-detection theory, applications of sign-detection formalism to information retrieval on MEDLINE database, and a…

Proposes a single underlying structure for the production of a variety of computer index displays, using a networking system which represents both concepts and links by nodes. Desirable characteristics of index displays are outlined, and algorithmic extraction of subnetworks for local use is discussed. References are included. (Author/BK)

Discusses the interpretation of nominal compounds in the context of natural language processing for information retrieval. Knowledge-intensive algorithms that can successfully interpret compounds found in technical documents are described, and experiments are reported that indicate these algorithms may be unnecessary for improving retrieval…

Proposes a new learning algorithm to improve the retrieval effectiveness of the search system used in the hypertext environment using an extended Boolean model with links to improve the ranking of retrieved items. Highlights include the basic retrieval scheme, the learning scheme, and a review of basic probabilistic retrieval models. (Contains 32…