Section 9.4

30. Who will you vote for? A simple random sample of 1500 voters were surveyed and asked whether they were planning to vote for the incumbent mayor for re-election. Seven hundred ninety-eight of them replied that they were planning to vote for the mayor. The mayor claims that more than half of all voters are planning to vote for her. To test this claim, a test of the hypotheses H₀: p = 0.5 versus H₁: p > 0.5 is performed.

a.Show that the P-value is 0.007.

b.The P-value is very small, so H0 is rejected. A pollster claims that because the P-value is very small, we can be fairly certain that the population proportion p is greater than 0.5, but we cannot be certain that it is a lot greater. Is this a correct interpretation of the P-value?