A TWO-STEP SAMPLE SIZE PROBLEM.
COLORADO STATE UNIV FORT COLLINS
Pagination or Media Count:
A problem in sampling is given in which an estimator of the mean of a normal population is determined such that the estimator deviates from the true population parameter by less than a given percentage of the true parameter with at least a certain specified probability. The problem is solved in the multi-step framework in which a minimum total sample size is to be attained. Certain assumptions on the existence of an upper bound on the coefficient of variation or a known positive lower bound on the mean are made. One, two and three step procedures are developed, of which the two-step process emerges as the most practical. A feasibility study is conducted using a high speed computer to determine, for a given confidence level, the form of an expression for the sample size as a function of the sufficient statistics mean and standard deviation of the first sample.