
Accession Number : AD0653189
Title : STUDIES IN RESEARCH METHODOLOGY. VII. THE CENTRAL LIMIT EFFECT FOR TWO DOZEN POPULATIONS AND ITS CORRELATION WITH POPULATION MOMENTS.
Descriptive Note : Final rept., Dec 64Oct 66,
Corporate Author : AEROSPACE MEDICAL RESEARCH LABS WRIGHTPATTERSON AFB OHIO
Personal Author(s) : Bradley,James V.
Report Date : DEC 1966
Pagination or Media Count : 88
Abstract : The report shows the Central Limit Effect upon the sample mean for samples from each of 24 populations. The exact shape of each population is shown graphically and its standardized central moments are given. Along with each population is shown the nonrobustness of its sample mean at both left and right tailed nominal alpha's of .50, .40, .30, .20, .10, .05, .025, .01, .005, .001, and .0005 for N's of 2, 4, 8, 16, 32, 64, 128, 256, 512, and 1024, thus depicting the Central Limit Effect in considerable detail. It is shown that the nonrobustness of the sample mean is strongly correlated with the departure of the 3rd and 4th standardized central moments of the sampled populations from their values for a normal distribution. When the population is appreciably asymmetric, the correlation with the 3rd moment tends to be extremely strong, especially when N is moderately large. (Author)
Descriptors : (*STATISTICAL TESTS, THEORY), (*POPULATION(MATHEMATICS), SAMPLING), STATISTICAL ANALYSIS, PSYCHOLOGY, HUMAN FACTORS ENGINEERING, CORRELATION TECHNIQUES
Subject Categories : Psychology
Statistics and Probability
Human Factors Engineering & Man Machine System
Distribution Statement : APPROVED FOR PUBLIC RELEASE