1) You are conducting a study on students' caffeine consumption. You believe that students might consume significantly more coffee during exam periods than prior to exam periods. To test this prediction, you conduct a pilot study asking a random sample of 10 students who drink coffee daily to report their average coffee consumption in March and a second (different) random sample to report their average coffee consumption in April. The results are shown in the table below. (20 marks) March (X-M1) X-M2 (X-M2) 8 April 10 X-M1 10 12 10 20 15 15 10 20 20 14 11 20 11 14 10 20 25 25 = b) Repeat the example except this time, each row represents a single participant measured twice, once in March and a second time during the exam period in April. Again, use a two-tailed test and alpha = .05. (20 marks) D D-MD (D-MD) March 8 April 10 10 12 10 20 15 15 10 20 20 14 11 20 11 14 10 20 25 25 = c) Compare the outcomes of the tests in parts (a) and (b). What can you conclude about the power of dependent and independent designs? Why is this the case? (3 marks) d) Calculate and compare Cohen's d for both the independent t-test and the dependent t-test. Why does the effect size change? (8 marks) e) Calculate and compare the 95% confidence interval for the independent t- test and the dependent t-test. Why is there a difference in the intervals? (8 marks)