57
Complex Samples Logistic Regression
All3-way. Creates all possible three-way interactionsof the selected variables.
All4-way. Creates all possible four-way interactionsof theselected variables.
All5-way. Creates all possible five-way interactionsof the selected variables.
NestedTerms
Youcan build nested terms for your model in this procedure. Nestedterms are usef ul for modeling
the effect ofa factor or covariate whose values do not interact with the levels of another factor.
Fore xample, a grocerystore chain may follow the spending habits of its customers at several store
locations. Since each customer frequents only one of these locations, the Customer effect can be
said to be nested withinthe Store location effect.
Additionally,you can include interaction effects, such as polynomial terms involving the same
covariate, or add multiple levelsof nesting to the nested term.
Limitations. Nested terms have the following restrictions:
All factors withinan interaction must be unique. Thus, if Ais a factor,then specifying A*A
is invalid.
All factors withina nested effect must be unique. Thus, if Ais a factor,then specifying A(A)
is invalid.
No effect can be nested within a covariate. Thus, if Ais a factor and Xis a covariate, then
specifying A(X) is invalid.
Intercept. The intercept is usuallyi ncludedin the model. If you can assume the data pass through
the origin, you can exclude the intercept. Even if you include the intercept in the model, you
can choose to suppress statistics related to it.
Complex Samples Logistic Regression Statistics
Figure 10-4
Logistic Regression Statistics dialog box
ModelFit. Controls the display of statistics that measure the overallmodel performance.