10.7 Swedish study test Refer to the previous exercise.

a. State the hypotheses that were tested.

b. Explain how to interpret the P-value for the test.

c. Even though the difference between the sample proportions was larger than in the Physicians Health Study

(Examples 2–4), the P-value is larger (i.e., the test results are less statistically significant). Explain how this could be. (Hint: How do the sample sizes compare for the two studies? How does this affect the standard error and thus the test statistic and P-value?)

d. Report the P-value for the one-sided alternative hypothesis that the chance of death due to heart attack is lower for the aspirin group.