For the Pure Error DF, consider the cases where more than one observation has the same value for height. In general, if there are g groups having multiple rows with identical values for each effect, the pooled DF, denoted DFp, is as follows:
For the Pure Error SS, in general, if there are g groups having multiple rows with the same x value, the pooled SS, denoted SSp, is written as follows:
Because Pure Error is invariant to the form of the model and is the minimum possible variance, Max RSq is calculated as follows:
