1. The manager of a television station employs three different weather reporters (coded as 1-3) and has sur- veyed viewers to find out whether education level (coded as 1-4) might be related to the weather reporter the viewer prefers. For the results listed in data file XR13040, use the 0.05 level of significance in concluding whether weather reporter preference and education level might be related.
2. For a random sample of returns audited by the IRS, the data in file XR13041 describe the results according to the income category of the audited party (coded as 1 5 low, 2 5 medium, 3 5 moderate, and 4 5 high) and the type of IRS personnel who examined the return (coded as 1 5 revenue agent, 2 5 tax auditor, and 3 5 service center). At the 0.05 level, are we able to con- clude that the category of return is independent of the type of IRS examiner to which a return was assigned?
3. For the following data obtained from three independent samples, use the 0.05 level in testing H0: 7r1 5 7r2 5 7r3 versus H1: "At least one population proportion differs from the others."
n1 5 100, p1 5 0.20
n2 5 120, p2 5 0.25
n3 5 200, p3 5 0.18
4. For the following data obtained from four independent samples, use the 0.025 level in testing H0: 7r1 5 7r2 5 7r3 5 7r4 versus H1: At least one popula- tion proportion differs from the others.
n1 5 150, p1 5 0.30
n2 5 80, p2 5 0.20
n3 5 140, p3 5 0.25
n4 5 50, p4 5 0.26
5. For three independent samples, each with n 5 100, the respective sample proportions are 0.30, 0.35, and 0.25. Use the 0.05 level in testing whether the three population proportions could be the same.