Suppose you want to determine whether meditation can cause a decrease in pulse rate. You randomly select 15 students, teach them a meditation technique, and then measure their pulse rates before and after meditation. Which test(s) should you choose for each situation?

a. Assume that your analysis shows that the differences in pulse rates are Normally distributed.

b. Assume that the distributions of differences in pulse rates are strongly skewed.

Choose from the following tests, as appropriate: paired t-test, sign test, two-sample t test, and Mann-Whitney test. There may be two acceptable choices.