The Hepatitis Knowledge Base (text of prototype information system) was used for modifying and testing "A Navigator of Natural Language Organized (Textual) Data" (ANNOD), a retrieval system which combines probabilistic, linguistic, and empirical means to rank individual paragraphs of full text for similarity to natural language queries…

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)

Data on 2,380 searches of online information retrieval systems are analyzed using a mathematical model to determine the relationship between two measures of effectiveness--documents read and relevant references. The nature and relative merits of these two variables are discussed, as well as the findings, and seven references are listed. (RBF)

The goal of this project was to find ways of enhancing the efficiency of searching machine readable data bases. Ways are sought to transfer to the computer some of the tasks that are normally performed by the user, i.e., to further automate information retrieval. Four experiments were conducted to test the feasibility of a sequential processing…

A comparative study of the cost effectiveness of retrospective manual and on-line bibliographic searching is described. Individual task times for question analysis, searching, photocopying, shelving and output distribution were measured, and component costs for labor, information, reproduction, physical space and telecommunications calculated. The…

Examines how online versions of databases vary on different systems. Differences are grouped into three categories: obvious differences, including easily available information such as updating, dates covered, and price; database choice, including subfile structure, field structure, and content; and system choice, including support and system…

This update of 1978 bibliometric study of online retrieval literature reveals that: literature has continued to grow, reaching peak annual output (504 papers) in 1981; conference literature has become centralized in four major proceedings; online retrieval papers have appeared in 479 journals; and 31 authors have contributed 10 or more papers.…

This collection of 39 papers represents the majority of presentations made at the ASIS Mid-Year Meeting at Syracuse University, May 19-21, 1977. Contents are arranged in alphabetical order by first author. The number preceding the author's name coincides with the numbered sequence of presentations in the program bulletin for the meeting. This…

In contrast to the usual approach in computer-based reference services, which is to go into a specific data base to retrieve citations to material on a specific, narrowly-defined topic, this report demonstrates how such services could be useful in a broad approach to a complex subject, using an investigation of trends in the world aluminum…

Computer-based information search services (ISSs) of the type that provide online literature searches are analyzed from a systems viewpoint using a continuous simulation model. The methodology applied is "system dynamics," and the system language is DYNAMO. The analysis reveals that the observed growth and stagnation of a typical ISS can…

An analysis of computer-based search services (ISSs) from a system's viewpoint, using a continuous simulation model to reveal growth and stagnation of a typical system is presented, as well as an analysis of decision making for an ISS. (Author/MBR)

Defines relationship between user profile and user query in terms of relationship between clusters of documents retrieved by each, and explores the expression of cluster similarity and cluster overlap as linear functions of similarity existing between original pairs of profiles and queries, given the desired retrieval threshold. (23 references)…

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…

Describes study of chemists in the Chemistry Division, Organic Research Laboratory, Eastman Kodak Company, as end-user searchers on the DIALOG system searching primarily the "Chemical Abstracts" database. Training, level of use, online browsing, types of searches, satisfaction, costs, and value of end-user searching are highlighted.…

Zipfian laws for frequency distributions of word pairs and longer phrases are derived from text sample analysis. From crossing of Zipfian curves, it is deduced that number of multi-word phrases that occur frequently in text is surprisingly small, of same order of magnitude as number of individual word-types. (8 references) (EJS)