fit.mult: Fits a multiplicative relative risk model to interval...

In Epi: A Package for Statistical Analysis in Epidemiology

Description

Utility function.

The model fitted assumes a piecewise constant baseline rate in intervals specified by the argument breaks, and a multiplicative relative risk function.

Usage

  fit.mult( 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.

Details

The model is fitted by alternating between two generalized linear models where one estimates the underlying rates in the intervals, and the other estimates the log-relative risks.

Value

A list with three components:

rates	A glm object from a binomial model with log-link, estimating the baseline rates.
cov	A glm object from a binomial model with complementary log-log link, estimating the log-rate-ratios
niter	Nuber of iterations, a scalar

Author(s)

Martyn Plummer, [email protected], Bendix Carstensen, [email protected]

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.

See Also

Icens fit.add

Examples

  data( HIV.dk ) 
  

Epi documentation built on March 18, 2018, 1:41 p.m.