Kauermann, Göran; Tutz, Gerhard
(2000):
Semiparametric Modeling of Ordinal Data.
Collaborative Research Center 386, Discussion Paper 193
|
![[img]](https://epub.ub.uni-muenchen.de/1583/1.hassmallThumbnailVersion/paper_193.pdf)  Preview |
|
353kB |
Abstract
Parametric models for categorical ordinal response variables, like the proportional odds model or the continuation ratio model, assume that the predictor is given as a linear form of covariates. In this paper the parametric models are extended to a semiparametric or partially parametric form where parts of the covariates are modeled linearly and parts are modeled as unspecified but smooth functions. Estimation is based on a combination of local likelihood and profile likelihood and asymptotic properties of the estimates are derived. In a simulation study it is demonstrated that the profile likelihood approach is to be preferred over a backfitting procedure. A data example shows the applicability of the models.