Describes a computerized information retrieval system that uses three agglomerative hierarchic clustering algorithms--single link, complete link, and group average link--and explains their implementations. It is noted that these implementations have been used to cluster a collection of 12,000 documents. (LRW)

Explains, with supporting figures and flowcharts of programing logic, two search strategies introduced to the MORPHS System since 1976: one that employs the normal Boolean operators in strings without bracketing or in the form of marked steps, and one that treats a string of keywords as a compound word. (Author/JD)

Presents a mathematical theory that can be used to define concentration places of objects within unordered classes. The application to research on the evolution of journals and subject areas is illustrated, and an online method of calculating concentration evolution is described. (1 references) (CLB)

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)

Presents principles for determining profile of a system user based on analysis of co-occurrence of index terms in queries and pertinent documents. A procedure for determining index term weights, the information value of which depends on the degree of homogeneity of system users, is introduced. Three references are cited. (EJS)

Following a discussion of derivative versus assignment indexing, use of roles, and concept behind Preserved Concept Indexing System, features of PERMDEX (microcomputer program to assist in creation of permuted printed index) are described including indexer input and prompts, the shunting algorithm, and sorting and printing routines. Fourteen…

Presents an algorithm for use in online information retrieval which will generate a list of bibliographic citations derived from a preselected relevant document and which measures the relatedness of retrieved items to the preselected document. A test of the algorithm in retrieving medical literature is described. Two figures are included. (JL)

Analyzes the formal properties, structural consequences, similarities, and differences of link indicators, brackets, and cohesion separators in the query languages employed in information retrieval. Eleven figures, a 32-item reference list, and appendices on Extended Backus Notation and the formal definition of the Formal Relevance Language are…

Describes an indexing technique based on overlapping word fragments as reference strings that are linked in a directed graph structure which makes possible exact match-, partial match-, and masked-partial match-retrieval and indicates search strategies for each case. Eight figures, two tables, and nine references are provided. (RBF)

Presents a theoretical rationale for employing a form of information retrieval algorithm that helps searchers better navigate through large document collections by continually revising probability estimates for document subsets. The algorithm avoids assumptions of index term independence and predicts relevance more accurately with increasing…

This paper describes an intelligent spelling error correction system for use in a word processing environment. The system employs a dictionary of 93,769 words and, provided the intended word is in the dictionary, it identifies 80 percent to 90 percent of spelling and typing errors. Nine references are cited. (Author/EJS)

Discussion of a new method of index term dictionary compression in an inverted-file-oriented database highlights a technique of word coding, which generates short fixed-length codes obtained from the index terms themselves by analysis of monogram and bigram statistical distributions. Substantial savings in communication channel utilization are…

Reports algorithm for calculation of term discrimination values that is sufficiently fast in operation to permit use of exact values. Evidence is presented to show that relationship between term discrimination and term frequency is crucially dependent upon type of inter-document similarity measure used for calculation of discrimination values. (13…

Presents a dynamic model of user behavior when scanning an information storage and retrieval system output list, compares rules for determining the user's optimum stopping point, presents an algorithm for implementing the Bayesian model, and discusses implications for retrieval system design. Provided are 13 figures and 15 references. (Author/RBF)

Explores potential of mathematical theory of communication for information science and examines question of how to encode a message at time it is encountered for subsequent recall. Examples of problem, a prototype computer program and experiment, coding as embedding in associational nets, and nature of information are discussed. (Nine references.)…