SPSS® 12.0 Command Syntax Reference

GENLOG 615
• The saved variables are pertinent to cells in the contingency table, not to individual
observations. In the Data Editor, all cases that define one cell receive the same value. To
make sense of these values, you need to aggregate the data to obtain cell counts.
Example
GENLOG A B
/SAVE PRED (PREDA_B)
/DESIGN = A, B.
• SAVE saves the predicted values for two independent variables A and B.
• The saved variable is renamed PREDA_B and added to the working data file.
DESIGN Subcommand
DESIGN specifies the model to be fit. If DESIGN is omitted or used with no specifications, the
saturated model is produced. The saturated model fits all main effects and all interaction effects.
• Only one design can be specified on the subcommand.
• To obtain main-effects models, name all of the variables listed on the variables
specification.
• To obtain interactions, use the keyword BY or an asterisk (*) to specify each interaction, for
example, A BY B or C*D. To obtain the single-degree-of-freedom partition of a specified
factor, specify the partition in parentheses following the factor (see the example below).
• To include cell covariates in the model, first identify them on the variable list by naming
them after the keyword WITH, and then specify the variable names on DESIGN.
• Effects that involve only independent variables result in redundancy. GENLOG removes
these effects from the model.
• If your variable list includes a cell covariate (identified by the keyword WITH), you cannot
imply the saturated model by omitting DESIGN or specifying it alone. You need to request
the model explicitly by specifying all main effects and interactions on DESIGN.
Example
COMPUTE X=MONTH.
GENLOG MONTH WITH X
/DESIGN X.
• This example tests the linear effect of the dependent variable.
• The variable specification identifies MONTH as a categorical variable. The keyword WITH
identifies X as a covariate.
• DESIGN tests the linear effect of MONTH.
Example
GENLOG A B
/DESIGN=A.
GENLOG A B
/DESIGN=A,B.