Each pair of graphs in Fig. 10.8 shows the distributions of a variable on two populations. Suppose that, in each case, you want to perform a small-sample hypothesis test based on independent simple random samples to compare the means of the two populations. In each case, decide which, if any, of the following tests is preferable: the pooled t-test, the nonpooled t-test, or the Mann-Whitney test. Explain your answers.

Transcribed Image Text:

(a) (b) (c) (d)