Comparison of two Web page designs. You want to compare the daily number of hits for two different MySpace page designs that advertise your new indie rock band. You assign the next 30 days to either Design A or Design B, 15 days to each.
(a) Would you use a one-sided or two-sided significance test for this problem? Explain your choice.
(b) If you use Table D to find the critical value, what are the degrees of freedom using the second approximation?
(c) If you perform the significance test using α = 0.05, how large (positive or negative) must the t statistic be to reject the null hypothesis that the two designs result in the same average number of hits?