Selecting the Normal Population with the Smallest Coefficient of Variation

SYNOPTIC ABSTRACT

We consider the problem of selecting the normal population with the smallest coefficient of variation, which is a natural goal when the means as well as the variances of the populations are unknown and unequal. The indifference-zone approach (Bechhofer 1954) to this problem has been previously considered by Choi, Jeon and Kim (1982). We review their selection procedure and provide tables of sample sizes for it. Next we consider the subset selection approach of Gupta (1956, 1965). We propose a natural selection procedure, derive its least favorable configuration and provide tables of critical constants. An example is given to illustrate the two procedures.

Keywords and Phrases:

• Indifference-zone approach
• Noncentral t-distribution
• Subset selection approach
• Unequal variances