Question

If you are comparing the center of two populations, the sample size is less than 10, and there are a few outliers, the best test is:

a) Z test

b) one-sample T test

c) two-sample T test

d) Mann-Whitney Test

Answer 1

Answer:

d) Mann-Whitney Test

Explanation:

The Z test can not be used because the population should be normally distributed with the known population standard deviation

The one-sample T-test can not be used because we are comparing two population mean

The two-sample T-test can not be used because the population should be approximately normally distributed (such that sample size should be at least 30) and no outlier

The Mann-Whitney test will be used because this is a nonparametric test that doesn't require the assumption of normal distribution and can be used with the data set of small sample size with outliers.