A statistical description of a text retrieval system allows the derivation of a unique and measurable performance criterion that, in turn, may be used in discussing various parameters of systems performance. (Author/PF)

Swets' theory of information retrieval allows the threads of document weighting formulae, probabilistic measures of effectiveness, and management theory, to be woven into a coherent pattern. Benefits are: the beginnings of a quantitative description of retrieval languages; destinction between retrieval systems and language; and question generality…

Proposes an alternative methodology for handling queries with weighted search terms or search criteria in a fuzzy environment as a means of improving the performance of information retrieval systems. (EM)

Reports on the validity of the Multiple Poisson (nP) model of word distribution in full-text document collections. A practical algorithm for determining whether a certain word is distributed according to an nP distribution and the results of a test of this algorithm in three different document collections are described. (14 references) (KRN)

This report explains the following mathematical techniques which may be used for relating search requests to documents contained in a library: (1) Boolean Algebraic Retrieval, (2) Linear Statistical Retrieval, (3) Statistical Association Techniques for expanding a query and/or for expanding the set of retrieval documents, (4) Vector Space…

RESULTS OF FIFTY DIFFERENT RETRIEVAL METHODS AS APPLIED IN THREE EXPERIMENTAL RETRIEVAL SYSTEMS WERE SUBJECTED TO AN ANALYSIS SUGGESTED BY STATISTICAL DECISION THEORY. THE ANALYSIS USES A PREVIOUSLY-PROPOSED MEASURE OF EFFECTIVENESS AND DEMONSTRATES ITS SEVERAL PROPERTIES. SOME OF THESE PROPERTIES ARE--(1) IT ENABLES THE RETRIEVAL SYSTEM TO…

Examines some questions arising in connection with the application and usefulness of Bradford's Law, which describes the dispersion of articles on a particular subject among journal titles. (Author)

Derives the underlying structure of the Zipf distribution, with emphasis on its application to word frequencies in the inverted files of automatic bibliographic systems, and applies the Zipfian model to the National Library of Medicine's MEDLINE database. An appendix on the Zipfian mean and 12 references are included. (Author/JL)

THE ABC (APPROACH BY CONCEPT) SYSTEM FOR STORAGE AND RETRIEVAL OF SCIENTIFIC AND TECHNICAL INFORMATION HAS BEEN SUBJECTED TO AN EXTENSIVE PERFORMANCE TEST. IN LI 000 318 THE TEST PROGRAM AND SETUP WAS DESCRIBED AS WELL AS THE METHODOLOGY, AND IN THE SECOND REPORT, LI 000 317, A PRELIMINARY STATISTICAL EVALUATION OF THE TEST RESULTS WAS GIVEN. THIS…

The objectives of this research were to investigage (1) the feasibility of an index simulator, and (2) the use of a sequential analysis model for the automatic classification of documents. Index simulation was studied in general for various types of indexes, and in depth for the simulation of an inverted coordinate index to a document collection…

Discusses methods of weighting of descriptors in document search patterns together with the concept of relative indexing and conditions which should be satisfied by descriptor weight. A procedure for modifiying document search patterns based on users' informational needs and opinions is outlined, and examples are given. Sixteen references are…

AFTER A BRIEF SUMMARY OF THE TEST PROGRAM (DESCRIBED MORE FULLY IN LI 000 318), THE STATISTICAL RESULTS TABULATED AS OVERALL "ABC (APPROACH BY CONCEPT)-RELEVANCE RATIOS" AND "ABC-RECALL FIGURES" ARE PRESENTED AND REVIEWED. AN ABSTRACT MODEL DEVELOPED IN ACCORDANCE WITH MAX WEBER'S "IDEALTYPUS" ("DIE OBJEKTIVITAET…

As the first of two papers delineating the design of Massachusetts' Management and Information System for Occupational Education (MISOE), these specific dimensions of MISOE structure and function are considered: (1) the distinction between economic and noneconomic analysis, (2) distinctions among census, sample, and other data, (3) the distinction…