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Chapter 10

Complex Samples Logistic Regression Odds Ratios

Figure 10-6

Logistic Regression Odds Ratios dialog box

The Odds Ratios dialog box allows you to display the model-estimated odds ratios for specified factors and covariates. A separate set of odds ratios is computed for each category of the dependent variable except the reference category.

Factors. For each selected factor, displays the ratio of the odds at each category of the factor to the odds at the specified reference category.

Covariates. For each selected covariate, displays the ratio of the odds at the covariate’s mean value plus the specified units of change to the odds at the mean.

When computing odds ratios for a factor or covariate, the procedure fixes all other factors at their highest levels and all other covariates at their means. If a factor or covariate interacts with other predictors in the model, then the odds ratios depend not only on the change in the specified variable but also on the values of the variables with which it interacts. If a specified covariate interacts with itself in the model (for example, age*age), then the odds ratios depend on both the change in the covariate and the value of the covariate.

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IBM SPSS COMPLEX SAMPLES 19 manual Complex Samples Logistic Regression Odds Ratios