In each of Exercises C.47–C.53, we have presented a study conducted using two-way ANOVA and have displayed corresponding computer output that contains a two-way ANOVA table, cell and marginal means, and interaction plots. For each exercise, use Procedure C.1 on page C-21 to perform a two-way ANOVA at the 5% individual significance level. (Note: Assume that it is reasonable to consider the assumptions for performing a two-way ANOVA met in each case.)
C.47 Household Income. The U.S. Bureau of the Census publishes data on money income of households by race and region in Current Population Reports. Independent samples of households yielded the following data on annual household income, in thousands of dollars. We performed a two-way ANOVA on the data. Output C.7 on page C-33 shows the resulting computer output and also supplies a table of cell and marginal means. Output C.8 on page C-33. shows the interaction plots.
OUTPUT C.7 ANOVA: INCOME versus RACE, REGION
Output for Exercise C.47 (and Exercise C.77)
OUTPUT C.8
Output for Exercise C.47
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Introductory Statistics (10th Edition)
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