In the August 12, 2007, issue of Parade magazine (which comes with the Sunday newspaper for millions of Americans), readers were asked to go online and vote on this question: Should the drinking age be lowered? The results were published in the October 7 issue; more than 14,000 readers voted, and 48% said "yes."
1. Employ these sample data to determine a 99% confidence interval for the population proportion who favor lowering the drinking age.
2. Report margin-of-error for this confidence interval.
3. Discuss why this interval is so narrow.
4. Without conducting a test of significance, what can you say about the p-value if you were to test whether the population proportion differs from one-half? Explain.
5. Does Parade's sampling method give you any reason to doubt that the confidence interval in question 1 is valid? Explain.