During May 2009, visitors to usatoday.com spent an average of 12.2 minutes per visit, compared to 11.0 minutes for visitors to washingtonpost.com. Assuming that file XR11030 contains the sample data underlying these results, use the 0.01 level of significance in exam- ining whether the population mean visiting times for the two sites might really be the same. Identify and interpret the p-value for the test. Construct and interpret the 99% confidence interval for the difference between the population means. Is the hypothesized difference (0.00) within the interval? Given the presence or absence of the 0.00 value within the interval, is this consistent with the findings of the hypothesis test?
Source: Jennifer Saba, "Average Time Spent on Top 30 Newspaper Web Sites Declines," editorandpublisher.com, June 22, 2009.