12.67 Contrasts of interest. Refer to Exercise 12.61 (page 692). Given the group means and F statistic, we can determine that MSE = 2.421. Use this value and the other information in Exercise 12.61 to do the following.

  1. (a) Test if there is a difference between the sexes.

  2. (b) Test if there is a difference between nationalities.

  3. (c) Explain why this study would have benefited from also including an Anglo female bargainer.