The F ratio is a ratio of the variability between groups to the variability within groups. To compute these values, we first have to compute what is called the sum of squares for each source of variability—between groups, within groups, and the total. The between-groups sum of squares is equal to the sum of the differences between the mean of all scores and the mean of each group’s score, which is then squared. This gives us an idea of how different each group’s mean is from the overall mean. The within-group sum of squares is equal to the sum of the differences between each individual score
...more
