PSY 350 Lecture Notes - Lecture 36: F-Distribution, Null Hypothesis
Document Summary
The sum of squares within and the sum of squares between add up to the total sum of squares, so: We also divide the degrees of freedom in the same way. To find the right f distribution, we need to know both the dfwithin and the dfbetween. Total degrees of freedom = n - 1 (just like a t-test) Degrees of freedom within treatments = n - k. Degrees of freedom between treatments = k - 1. In anova, we often say mean square instead of variance, but they are the same thing mean square (ms)=s2 = ss/df. Since we can find sswithin and ssbetween, and. Just as we did with t, we use the df (between and within!) to find the right f distribution from the family of f distributions. We set our level and use the f distribution to find the critical value of f to reject the null hypothesis.
