fit.add: Fit an addive excess risk model to interval censored data.
Description
Utility function.
The model fitted assumes a piecewise constant inensity for the
baseline, and that the covariates act additively on the rate scale.
Usage
fit.add( y, rates.frame, cov.frame, start )
Arguments
y
Binary vector of outcomes
rates.frame
Dataframe expanded from the original data by
expand.data, cooresponding to covariates for the rate
parameters.
cov.frame
do., but covariates corresponding to the
formula argument of Icens
start
Starting values for the rate parameters. If not supplied,
then starting values are generated.
Value
A glm object from a binomial model with log-link function.
References
B Carstensen: Regression models for interval censored
survival data: application to HIV infection in Danish homosexual
men. Statistics in Medicine, 15(20):2177-2189, 1996.
CP Farrington: Interval censored survival data: a generalized linear
modelling approach. Statistics in Medicine, 15(3):283-292, 1996.