Type: Package
Title: R2 Measure of Explained Variation under the Additive Hazards Model
Version: 0.1.0
Date: 2020-03-20
Author: Denise Rava
Maintainer: Denise Rava <drava@ucsd.edu>
Description: R^2 measure of explained variation under the semiparametric additive hazards model is estimated. The measure can be used as a measure of predictive capability and therefore it can be adopted in model selection process. Rava, D. and Xu, R. (2020) <doi:10.48550/arXiv.2003.09460>.
License: GPL-2
Encoding: UTF-8
LazyData: true
RdMacros: Rdpack
Imports: ahaz, pracma, zoo, caTools, survival, Rdpack (≥ 0.7)
NeedsCompilation: no
Packaged: 2020-04-06 19:38:37 UTC; Denise
Repository: CRAN
Date/Publication: 2020-04-07 15:20:02 UTC

Estimate R^2 for additive hazards model

Description

The function computes R^2 measure of explained variation under the semiparametric additive hazards model.

Usage

R2addhaz(data)

Arguments

data

a data.frame with survival data. The first column needs to be the censored failure time. The second column needs to be the event indicator, 1 if the event is observed, 0 if it is censored. The other columns are covariates.

Details

The semiparametric hazards model

\lambda(t | Z)=\lambda_0(t) + \beta Z

is fitted to the data. The R^2 measure of explained variation is then computed.

Value

R

R^2 measure of explained variation.

Author(s)

Denise Rava

References

Rava, D., Xu, R. "Explained Variation under the Additive Hazards Model", March 2020, arXiv:2003.09460

Examples

Z=runif(100,0,sqrt(3)) #generate covariates
u=runif(100,0,1)
t=-log(u)/as.vector((1+Z)) #generate failure time
status=rep(1,100) #censoring indicator
sd<-as.data.frame(cbind(t,status,Z)) #data frame of survival data
R2addhaz(sd)