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Complex Samples Ordinal Regression
Figure 11-1
Ordinal Regression dialog box
ESelect a dependent variable.
Optionally,you can:
Select variables forfactors 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.
Linkfunction. The link function is a transformationof the cumulative probabilities that allows
estimation of themodel. Fivelink functions are available, summarized in the following table.
Function Form Typicalapplication
Logit log( ξ/(1−ξ) ) Evenly distributed categories
Complementary log-log log(−log(1−ξ)) Highercategories more probable
Negative log-log −log(−log(ξ)) Lowercate gories 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