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This table displays the model-estimated marginal means and
standard errors of Amount spent
at the factor combinations of Gender and
Shopping style. This table is useful for
exploring the possible interaction effect between these two factors.
In this example, a male customer who makes purchases weekly is expected to
spend about $457.65, while one who makes purchases more often is expected
to spend $428.06.
A female customer who makes purchases weekly is
expected to spend $363.70, while one who makes purchases more often is expected
to spend $424.04. Thus, there is a difference
between "weekly" and "often" customers, depending upon the gender of
the customer.
This fact suggests an interaction effect between
Gender and
Shopping style.
If there were no interaction, you would
expect the difference between shopping styles to remain constant
for male and female customers. The interaction can be
seen more easily in the profile plots.
The profile plot is a visual representation of the marginal means table.
The factor levels of Shopping style are shown
along the horizontal axis.
Separate lines are produced for each level
of Gender.
Alternately, the factor levels of Gender
could be shown along the horizontal axis, with separate lines produced
for each level of Shopping style.
If there were no interaction effect, the lines in the table would be
parallel. Instead, you can see that the difference in spending between "weekly" and
"biweekly" customers is greater for male customers, as shown by the sharper rise
in the line.
The difference in spending between "weekly" and "often" customers
is greater for female customers, as the line for male customers slopes downward and
that for female customers slopes upward.
This is a strong interaction effect and is unlikely to be due to chance, but
you should check the tests of between-subjects effects for confirmation of
its significance.
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Estimated Marginal Means |