Hello! I need to perform a one-way ANOVA once using effect coding and once using reference coding for a categorical variable with four categories. However, I noticed that PROC GLM only allows reference coding... Additionally, after running the ANOVA, I need to perform orthogonal contrasts and verify that the contrasts produce an additive decomposition of the explained deviance. Which SAS procedure allows me to specify the coding scheme for categorical variables (effect coding vs. reference coding) in ANOVA? How can I define orthogonal contrasts and ensure they lead to an additive decomposition of the explained variance in the same procedure above? Any advice or example code would be greatly appreciated! ... View more