Statistics for the Behavioral Sciences by Frederick J. Gravetter, Larry B. Wallnau ISBN 10: 1305504917 ISBN 13: 9781305504912

404 CHAPTER 12 | Introduction to Analysis of Variance
Total
G 2
SS = S X 2 2
N
df = N 2 1
Between treatments
SS = SS total 2 SS within
T G
or SS =
2 2
S
n 2
N
df = k 2 1
SS
MS =
df
Within treatments
SS = SSS each treatment
df = N 2 k
MS = SS
df
FIGURE 12.11
Formulas for ANOVA.
F-ratio =
MS between treatments
MS within treatments
KEY TERMS
analysis of variance (ANOVA) (366)
factor (367)
levels (368)
experimentwise alpha level (370)
between-treatments variance (373)
treatment effect (373)
within-treatments variance (373)
F-ratio (373)
error term (374)
ANOVA summary table (380)
mean square (MS) (381)
distribution of F-ratios (384)
eta squared (η 2 ) (389)
post hoc tests (393)
pairwise comparisons (393)
Tukey’s HSD test (394)
Scheffé test (395)
Kruskal-Wallis test (400)
SPSS ®
General instructions for using SPSS are presented in Appendix D. Following are detailed
instructions for using SPSS to perform the Single-Factor, Independent-Measures Analysis
of Variance (ANOVA) presented in this chapter.
Data Entry
1. The scores are entered in a stacked format in the data editor, which means that all the
scores from all of the different treatments are entered in a single column (VAR00001).
Enter the scores for treatment #2 directly beneath the scores from treatment #1 with no
gaps or extra spaces. Continue in the same column with the scores from treatment #3, and
so on.
2. In the second column (VAR00002), enter a number to identify the treatment condition for
each score. For example, enter a 1 beside each score from the first treatment, enter a
2 beside each score from the second treatment, and so on.