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SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

SPSS® 12.0 Command Syntax Reference

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812 LOGISTIC REGRESSION<br />

CRITERIA Subcommand<br />

CRITERIA controls the statistical criteria used in building the logistic regression models. The<br />

way in which these criteria are used depends on the method specified on the METHOD subcommand.<br />

The default criteria are noted in the description of each keyword below. Iterations<br />

will stop if the criterion for BCON, LCON, or ITERATE is satisfied.<br />

BCON(value) Change in parameter estimates to terminate iteration. Iteration terminates<br />

when the parameters change by less than the specified value. The default is<br />

0.001. To eliminate this criterion, specify a value of 0.<br />

ITERATE Maximum number of iterations. The default is 20.<br />

LCON(value) Percentage change in the log-likelihood ratio for termination of iterations.<br />

If the log-likelihood decreases by less than the specified value, iteration terminates.<br />

The default is 0, which is equivalent to not using this criterion.<br />

PIN(value) Probability of score statistic for variable entry. The default is 0.05. The larger<br />

the specified probability, the easier it is for a variable to enter the model.<br />

POUT(value) Probability of conditional, Wald, or LR statistic to remove a variable. The<br />

default is 0.1. The larger the specified probability, the easier it is for a variable<br />

to remain in the model.<br />

EPS(value) Epsilon value used for redundancy checking. The specified value must be<br />

less than or equal to 0.05 and greater than or equal to 10 . The default is<br />

. Larger values make it harder for variables to pass the redundancy<br />

check—that is, they are more likely to be removed from the analysis.<br />

12 –<br />

10 8 –<br />

CUT(value) Cutoff value for classification. A case is assigned to a group when the predicted<br />

event probability is greater than or equal to the cutoff value. The<br />

cutoff value affects the value of the dichotomous derived variable in the<br />

classification table, the predicted group (PGROUP on CASEWISE), and the<br />

classification plot (CLASSPLOT). The default cutoff value is 0.5. You can<br />

specify a value between 0 and 1 (0 < value < 1).<br />

Example<br />

LOGISTIC REGRESSION PROMOTED WITH AGE JOBTIME RACE<br />

/CATEGORICAL RACE<br />

/METHOD BSTEP<br />

/CRITERIA BCON(0.01) PIN(0.01) POUT(0.05).<br />

• A backward stepwise logistic regression analysis is performed for the dependent variable<br />

PROMOTED and the independent variables AGE, JOBTIME, and RACE.<br />

• CRITERIA alters four of the statistical criteria that control the building of a model.<br />

• BCON specifies that if the change in the absolute value of all of the parameter estimates<br />

is less than 0.01, the iterative estimation process should stop. Larger values lower the<br />

number of iterations required. Notice that the ITER and LCON criteria remain unchanged<br />

and that if either of them is met before BCON, iterations will terminate. (LCON can be set<br />

to 0 if only BCON and ITER are to be used.)

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