Mean Sum Of Squares (MSQ)

The mean sum of squares associated with error variation (MSE) is the ratio of the sum of squares associated with error variation to the degrees of freedom.   In regression analysis the MSE is the variance term.  The MSR is used to specify the average amount of variation explained about the regression line by the model parameters.

        MSE = SSE / df_SSE

        MSR = SSR / df_SSR

where, df is degrees of freedom.