Information Technology Reference
In-Depth Information
Figure 8.7
The main
GLMUnivariate
dialog window.
over to the
Dependent Variable
panel and click
gender
and
reside
over
to the
Fixed Factor(s)
panel. We will first run the omnibus analysis to
determine which effects are significant. Based on those results we will
then determine which post-ANOVA analyses we will perform.
Click the
Options
pushbutton to reach the
Options
dialog window
shown in Figure 8.8. The top half of the window displays the
Esti-
mated Marginal Means
. Such means are unweighted in that they rep-
resent the average of the group means without taking into account the
sample sizes on which those means were based. SPSS presents these in
separate tables and uses these estimated marginal means to plot the
interaction. We will click over the two main effects and the interac-
tion (
gender
,
reside
,
gender
reside
) from the left panel labeled
Fac-
tor(s) and Factor Interactions
to the right panel labeled
Display Means
for
.
The bottom half of the
Options
window displays the observed means.
Under the
Display
heading, we check
Descriptive statistics
to obtain
the observed means and standard deviations of the groups. It is also
necessary to determine if the data meet the homogeneity of variance
assumption, that is, the assumption that the conditions in the study
(the combinations of the levels of the independent variables) have equal
variances on the dependent variable), and so we check
Homogeneity
tests
.
∗
