Hello I have an experiment with two factors MANAGEMENT and REGION. And I have three MANAGEMENT types and three REGIONS. Like this. REGION: A, B and C MANAGEMENT: N, P, ST the independent variable is called PHt I have set the aov in R in two possible ways. The first model I understand, but I do not understand how the second model set the df for each variable. I understood that the second model is the most correct for a two-way ANOVA without repetition, is that correct?: - aov(PHt~REGION+MANAGEMENT+REGION*MANAGEMENT, data=data) - aov(PHt~REGION*MANAGEMENT+Error(subject/(REGION*MANAGEMENT)),data=data) I attach the results of the two models. Best regards Rosario