The degrees of freedom are found by subtracting "1" from the amount of information needed to obtain the sums of squares. The formulas are presented below. The letter "a" is the number of levels/groups in Factor A; the letter "b" is the number of levels/groups in Factor "B", and the letter "N" is the total number of scores/subjects in the experiment.

We are now ready to calculate our mean squares and prepare our summary table.