Author : Mat Yusoff Abdullah

Summary : The objective of the paper is the determination of the nature of bias and distribution of the coefficient of variation from small samples. The study involves machine generation of 1,000 samples of size 4 from each of normal and gamma populations with different parameters. Using the actual 1970 population counts of the 14 towns of Zambales, 18 towns of Nueva Vizcaya and 29 towns of Rizal, all simple random samples of size 3 and 5 were drawn and the magnitudes of the bias and distribution of the sample coefficient of variation were observed. The distribution of the parent population affects the distribution of the sample coefficient of variation. In the case of Zambales, its bimodal town population also gave rise to bimodally distributed sample coefficients of variation. The extreme skewness and large variability of the town populations of Rizal resulted in a seriously biased sample coefficient of variation.