For Exercises 15.1 to 15.3, see pages 15-6 to 15-7; for 15.4 to 15.6, see page 15-10; for 15.7, see pages 15-12 to 15-13; for 15.8 to 15.10, see page 15-15; for 15.11, see page 15-16; for 15.12 and 15.13, see page 15-18; and for 15.14 to 15.16, see pages 15-20 to 15-21.

Question 15.1

15.1 What’s wrong?

For each of the following, explain what is wrong and why.

  1. A two-way ANOVA is used when there are two outcome variables.
  2. In a ANOVA, each level of Factor A appears with only two levels of Factor B.
  3. The FIT part of the model in a two-way ANOVA represents the variation that is sometimes called error or residual.
  4. You can perform a two-way ANOVA only when the samples sizes are the same in each cell.

15.1

(a) A two-way ANOVA is used when there are two factors (explanatory variables) not outcomes. (b) Each level of Factor A appears with each level of Factor B. (c) This is true for the RESIDUAL part of the model, not the FIT. (d) The sample sizes in each cell can be different.