The following data represent the results from an independent-measures study comparing three treatments.
a. Compute SS for the set of 3 treatment means (Use the three means as a set of n=3 scores and compute SS) Treat the means as if they are scores and compute their mean as you would calculate the mean for the scores. Then obtain the sum of squared deviations. Most students get confused about this. Just use the three means that are given, obtain the average for them, then obtain the deviations (the mean - the average) in each case. Then square these deviations and then add them up.
b. Using the result from part a, compute n (SSmeans). Note that this value is equal to SSbetween (see Equation 13.6).
c. Now, compute SSbetween with the computational formula using the T values (Equation 13.7). You should obtain the same result as in part b.
I II III
n=10 n=10 n=10
M=2 M=3 M=7
T=20 T=30 T=70
A Complete, Neat and Step-by-step Solution is provided in the attached file.