Accession Number : AD0625027

Title :   UNITERMS AND THE LEARNING CURVE,

Corporate Author : AMERICAN CHIROPRACTIC ASSOCIATION WASHINGTON D C DEPT OF RESEARCH AND STATISTICS

Personal Author(s) : Higley,Henry G.

Report Date : 1965

Pagination or Media Count : 15

Abstract : Studies were made of the characteristics of the input of uniterms, for coordinate indexing, over a short period of time, more specifically, the frequency of uniterm cards with a given number of entries derived from input. For a set of 500 documents of the American Chiropractic Assn. input over 3 months, there were 258 uniterm cards with 2755 accession numbers, i.e. 10.68 average of accession numbers per uniterm card and 5.51 average number of uniterms per document. The frequency of uniterms with a given number of entries closely followed the learning or progress curve y = ax to the b power, with the exception of x = 1. Study of similar data from the uniterm index of the Pacific Aeronautical Library of the American Institute of Aeronautics gave similar results. In this curve, the x axis is the number of documents/uniterm card, the y axis the number of uniterm cards. The parameter a is thought to depend on the size of the collection, while b is a measure of the rate of change of y for values of x and for these collections is thought to be a function of the characteristics of the sets of documents and of the methods of analysis and coding. The class x = 1 may be interpreted as representing new concepts or older concepts being replaced by new ideas.

Descriptors :   (*SUBJECT INDEXING, CURVE FITTING), STATISTICAL TESTS

Subject Categories : Information Science

Distribution Statement : APPROVED FOR PUBLIC RELEASE