Suppose that for (uncounseled) sexually active individuals the probability of acquiring an STD in a 6-month period is 10%.
(a) Using your interval computed in Exercise 9.S.21, is there compelling evidence that the 6-month STD probability is different for those who receive counseling?
(b) Using the data from Exercise 9.S.21, conduct a nondirectional chi-square test to determine if the 6-month STD rate is different for counseled individuals compared to the uncounseled population.
(c) Do your answers to parts (a) and (b) agree? Explain.