A psychology department secretary notices that the average number of student complaints the department receives per week is 1.4 (m = 1.4). He notices that the department has made some poor policy changes recently and wants to see if the number of complaints that the department receives has increased. He records the following number of complaints that came in per week for 8 weeks: 2, 4, 3, 5, 4, 1, 1, and 4.

(a) Test the hypothesis that the number of complaints has increased using a .05 level of significance. State the value for the test statistic and the decision to retain or reject the null hypothesis.

(b) Compute effect size using estimated Cohen's d.