Author/Editor		Gregori, Dario; Rosato, Rosalba; Ciccone, Giovannino; Lusa, Lara
Title		Parameterized link functions in generalized linear random effect models
Type		članek
Vol. and No.		, št. Vol. 17
Publication year		2005
Volume		str. 97-107
ISSN		0204-9805 - Pliska. Pliiska
Language		eng
Abstract		In non-linear random effects some attention has been very recently devoted to the analysis of suitable transformation of the response variables separately (Taylor 1996) or not (Oberg & Davidian 2000) from the transformations of the covariates and, as far as we know, no investigation has been carried out on the choice of link function in such models. In our study we consider the use of a random effect model when a parameterized family of links (Aranda- Ordaz 1981, Prentice 1996, Pregibon 1980, Stukel 1988 and Czado 1997) is introduced. We point out the advantages and the drawbacks associated with the choice of this data-driven kind of modeling. Diffculties in the interpretation of regression parameters, and therefore in understanding the in uence of covariates, as well as problems related to loss of effciency of estimates and overfitting, are discussed. A case study on radiotherapy usage in breast cancer treatment is discussed.
Keywords		statistics response variable regression parameters statistika odvisna spremenljivka regresijski parameter