1. Why is the sample r alone sufficient for adequate interpretation when the sample size is quite large (say over 300 or 400 cases), whereas an interval estimate is recommended for smaller samples?
2. For a sample of her 10 students, an instructor correlates "test anxiety" (X) with "percent correct" (Y) on the recent midterm. The data are as follows:
(a) Would the Pearson r be an appropriate measure of association for these data? (Explain.)
(b) What would be the statistical consequence of computing Pearson r from these data? (No calculations necessary.)