Bluman A.G. Elementary Statistics- A Step By Step Approach

646 Chapter 12 Analysis of Varianceclothing in shades of brown and yellow. Group 3 subjects were randomly shown people withclothing in shades of pink and orange. The results follow.Group 1 Group 2 Group 38 7 47 8 97 7 67 7 78 5 98 8 86 5 58 8 88 7 77 6 57 6 48 6 58 6 41. Use the Tukey test to test all possible pairwise comparisons.2. Are there any contradictions in the results?3. Explain why separate t tests are not accepted in this situation.4. When would Tukey’s test be preferred over the Scheffé method? Explain.See page 668 for the answers.Exercises 12–21. What two tests can be used to compare two means whenthe null hypothesis is rejected using the one-wayANOVA F test? The Scheffé and Tukey tests are used.2. Explain the difference between the two tests used tocompare two means when the null hypothesis is rejectedusing the one-way ANOVA F test.For Exercises 3 through 9, the null hypothesis wasrejected. Use the Scheffé test when sample sizes areunequal or the Tukey test when sample sizes are equal,to test the differences between the pairs of means.Assume all variables are normally distributed, samplesare independent, and the population variances are equal.3. Exercise 9 in Section 12–1.4. Exercise 12 in Section 12–1.5. Exercise 13 in Section 12–1.6. Exercise 16 in Section 12–1. No further testing should be done.7. Exercise 17 in Section 12–1.8. Exercise 18 in Section 12–1.9. Exercise 20 in Section 12–1.For Exercises 10 through 13, do a complete one-wayANOVA. If the null hypothesis is rejected, use either theScheffé or Tukey test to see if there is a significantdifference in the pairs of means. Assume all assumptionsare met.10. Weights of Digital Cameras The data consist ofthe weights in ounces of three different types of digitalcamera. Use a 0.05 to see if the means are equal.2–3 Megapixels 4–5 Megapixels 6–8 Megapixels6 14 198 11 277 15 2111 24 234 17 248 10 3311. Fiber Content of Foods The number of gramsof fiber per serving for a random sample of threedifferent kinds of foods is listed. Is there sufficientevidence at the 0.05 level of significance to concludethat there is a difference in mean fiber content amongbreakfast cereals, fruits, and vegetables?Breakfast cereals Fruits Vegetables3 5.5 104 2 1.56 4.4 3.54 1.6 2.710 3.8 2.55 4.5 6.56 2.8 48 35Source: The Doctor’s Pocket Calorie, Fat, and Carbohydrate Counter.12–18