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Complex Samples Ordinal Regression
Figure
Ordinal Regression dialog box
ESelect a dependent variable. Optionally, you can:
Select variables for factors and covariates, as appropriate for your data.
Specify a variable to define a subpopulation. The analysis is performed only for the selected category of the subpopulation variable, although variances are still properly estimated based on the entire dataset.
Select a link function.
Link function. The link function is a transformation of the cumulative probabilities that allows estimation of the model. Five link functions are available, summarized in the following table.
Function | Form | Typical application |
Logit | log( ξ / (1−ξ) ) | Evenly distributed categories |
Complementary | log(−log(1−ξ)) | Higher categories more probable |
Negative | −log(−log(ξ)) | Lower categories more probable |
Probit | Φ−1(ξ) | Latent variable is normally |
|
| distributed |
Cauchit (inverse Cauchy) | tan(π(ξ−0.5)) | Latent variable has many extreme |
|
| values |
