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Figure 15.28
Specifying the effects for which we wish to obtain least square means.
15.9 SAS OUTPUT OF THE OMNIBUS ANALYSIS
The least squares means are shown in Figure 15.29. The results of the
omnibus analysis are shown in Figure 15.30. The
F
ratios obtained through
SAS are similar to but not exactly the same as those produced by SPSS (see
Section 10.17) because of the two within-subjects factors in the design.
Examining the summary table informs us that most of the effects are
statistically significant.
15.10 PERFORMING THE POST-ANOVA ANALYSIS IN SAS
To perform the simple effects analysis in
SAS Enterprise Guide
, configure
the analysis as shown above. Then in the
Least Squares Post Hoc Tests
screen shown in Figure 15.31, in the
Effects to use
frame, set the three-
way interaction to
True
and all others to
False
. Then in the
Comparisons
frame, set
Show p-values for differences
to
All pairwise differences
and
set
Adjustment method for comparison
to
Bonferroni
.Click
Run
to
perform the analysis.