I have a question regarding the default contrasts anova() uses R. As far as I understand, the default setting in anova is, that each group/treatment condition is compared to the baseline group.

If I assume we have three treatment conditions A, B and C, and A is my baseline, I can now write down the ''group-contrast-table'' in terms of groups and dummy variables:

C1 C1 | product

A -1 -1 | 1

B 1 0 | 0

C 0 1 | 0

--------------------

0 0 1

Thus, these contrast are not orthogonal. Is this true? Where is my mistake?

Thanks