65
Complex Samples Ordinal Regression
Figure 11-1
Ordinal Regression dialog box
E Select 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 log(−log(1−ξ)) Higher categories more pro bable
Negative log-log −log(−log(ξ)) Lower categories more probable
Probit Φ
−1
(ξ) Latent va r iable is normally
distributed
Cauchit ( inve rse Cauchy) tan(π(ξ−0.5)) Latent va riable has many extrem e
values
