The way to isolate the variation due to the treatment conditions (also called effect) is to look at the means in each group, and the calculate the difference scores between each group mean and the gra...The way to isolate the variation due to the treatment conditions (also called effect) is to look at the means in each group, and the calculate the difference scores between each group mean and the grand mean, and then the squared deviations to find the sum for SSEffect. Remember, that the p-value represents the probability of getting the F value we observed or larger under the null (assuming that the samples come from the same distribution, the assumption of no differences).
