Refer to the previous exercise.
a. State the hypotheses that were tested.
b. Explain how to interpret the P-value for the test.
c. 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.
d. Even though the difference between the sample proportions was larger than in the Physicians Health Study (Examples 2–4), the results are less statistically significant. Explain how this could be. (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?)