Cochran Formula 1977. Krejcie and Morgans 1970 formula for determining sample size for categorical data will be briefly discus sed because it provides identical sample sizes in all cases where the researcher adjusts the t value used based on. Could the samples from the two domains have been drawn at random.
N0 Z square x pqe square. Which is valid where n 0 is the sample size Z 2 is the abscissa of the normal curve that cuts off an area αat. SONS 1977 ISBN 0-471-16240-X.
A formula similar to 267 is obtained for tests of significance if one frames the question.
You can always take a larger sample. However since this sample size exceeds 5 of the population 16790584 Cochrans 1977 correction formula should be used to calculate the final sample size. The variance reduces to Vy I s2Nn 1 I wsh2 58 Corollary 3. COCHRAN Professor of Statistics Emeritus Harvard University JOHN WILEY.
