Fox Module 16 Analysis of variance
One-way analysis of variance
Two-way analysis of variance
Patterns of means in two-way classification
Read Section 8.1, “One-way analysis of variance,” on pages 143-148. Know the difference between dummy regressors and deviation regressors. The regression results are the same, bur the interpretation of the regression coefficients differs.
Contrast the tables on pages 143 and 146.
Know the relation of the regression coefficients and groups means on pages 145-146.
Review the illustration on pages 147-148. The final exam problems compute the F-test from the sum of squares of the groups and residuals, test the degrees of freedom, or ask you to back into one of the figures.
Read Section 8.2, “Two-way analysis of variance,” on pages 149-154. Focus on the graphs, and the various ways the two dimensions interact.
The patterns of interaction affect actuarial analyses.
Illustration: Men have higher claim frequencies than women for auto accidents. But men also drive more and they drink more. Figuring out what class dimensions are important is not easy.