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.48 Golden Torch Cacti Lengths. Another variable Feldman and Crosswhite investigated in their study of Golden Torch cacti was total length of cuttings at the end of 16 months. Here are the data, in millimeters. We performed a two-way ANOVA on the data. Output C.9 on page C-34. shows the resulting computer output and also supplies a table of cell and marginal means. Output C. 10 on page C-34. shows the interaction plots.
OUTPUT C.9
Output for Exercise C.48 (and Exercise C.78)
ANOVA: LENGTH versus POLYMER, WATER
OUTPUT C.10
Output for Exercise C.48
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Introductory Statistics (10th Edition)
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