Question

The test-retest method is one way of establishing the reliability of a test. The test is administered, and then, at a later date, the same test is re-administered to the same individuals. The correlation coefficient is computed between the two sets of scores. The following test scores were obtained in a test-retest situation. (Give your answers correct to two decimal places.)

First Score	86	85	97	65	77	66	67	80	90	93
Second Score	79	73	60	62	80	68	87	58	56	88

(a) Find r.

(b) Set a 95% confidence interval for ρ.

Lower Limit
Upper Limit

Answer 1

First we have to find the correlation coefficient and then confidence interval for population correlation coefficient  $\rho$