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Complex Samples General Linear Model
The Estimated Means dialog box allowsyou to display the model-estimated marginal means for
levelsof factors and factor interactions specified in the Model subdialog box. Youcan also request
that the overall populationmean be displayed.
Term. Estimated means are computed for the selected factors and factor interactions.
Contrast. The contrast determineshow hypothesis tests are set up to compare the estimated means.
Simple. Comparesthe mean of each level to the mean of a specified level. This type of contrast
is useful when there is a control group.
Deviation. Compares the mean of each level (except a referencecategory) to the mean of all of
the levels (grand mean). The levels of the factor can be in any order.
Difference. Compares the mean of each level (except the first) to the mean of previous levels.
They are sometimes called reverse Helmert contrasts.
Helmert. Compares the mean of each level of the factor (except the last) to the mean of
subsequent levels.
Repeated. Compares the mean of each level (except the last) to the mean of thesubsequent
level.
Polynomial. Compares the linear effect, quadratic effect, cubic effect, and so on. The
first degree of freedom contains the linear effect across all categories; the second degree
of freedom, the quadratic effect; and so on. These contrasts are often used to estimate
polynomial trends.
ReferenceCategory. The simple and deviation contrasts require a reference category or factor
level against which the othersare compared.
Complex Samples General Linear Model Save
Figure 9-6
General LinearModel Save dialog box
SaveVariables. This group allows you to save the model predicted values and residuals as new
variables in the working file.