It is convenient to view the results of an analysis of variance in a summary table. The summary table for the example data is shown below.

Source df Ssq Ms F p Groups 2 8.000 4.000 3.60 0.071 Error 9 10.000 1.111 Total 11 18.000 1.636The first column contains the source of variation (or source for short). There are two sources of variation: differences among treatment groups and error. The second column contains the degrees of freedom (df). The df for groups is always equal to the number of groups minus one. The df for error is equal to the number of subjects minus the number of groups. The formulas for the degrees of freedom are shown below:

df

df

df

a is the number groups

N is the total number of subjects.

df