Class 7. Categorical variables: more than 2-groups.

Table of contents for Class 7

	199-202 ........ Discursive introduction.
	203-211 ........ Categorical variables with 2 groups revisited.
	213-221 ........ Categorical variables with more than 2 groups
                         (worked example).
           214-215 ..... Graphical diagnostics for fits to each group.
               216 ..... Parallel lines model.
               217 ..... Partial-F to test three groups at once.
               218 ..... Non-parallel lines model.
           219-220 ..... Checking residuals in categorical variable regression.