The following data are from an experiment comparing three different treatment conditions:
A B C
______________
0 1 2
2 5 5
1 2 6
5 4 9
2 8 8
_________________
T = 10 T = 20 T = 30
SS = 14 SS = 30 SS = 30
N = 15
ΣX² = 354
a. If the experiment uses an independent-measures design, can the researcher conclude that the treatments are significantly different? Test at the .05 level of significance.
b. If the experiment is done with a repeated-measures design, should the researcher conclude that the treatments are significantly different? Set alpha at .05 again.
c. Explain why the analyses in parts a and b lead to different conclusions.
