In this post we look at how we can compute the two-way ANOVA of a balanced design. The dataset is weightgain in package HSAUR and it shows the weight gains of rats put on four different diets, with two varying factors (the source of protein, which can be beef or cereal and the type which can be high or low).
The R Code and graphs (main effects, interactions) are shown in the link below.
Theo's Data Science Blog 