wald.test {timereg} | R Documentation |
Makes wald test
Description
Makes wald test, either by contrast matrix or testing components to 0. Can also specify the regression coefficients and the variance matrix. Also makes confidence intervals of the defined contrasts. Reads coefficientes and variances from timereg and coxph objects.
Usage
wald.test(
object = NULL,
coef = NULL,
Sigma = NULL,
vcov = NULL,
contrast,
coef.null = NULL,
null = NULL,
print.coef = TRUE,
alpha = 0.05
)
Arguments
object |
timereg object |
coef |
estimates from some model |
Sigma |
variance of estimates |
vcov |
same as Sigma but more standard in other functions |
contrast |
contrast matrix for testing |
coef.null |
which indeces to test to 0 |
null |
mean of null, 0 by default |
print.coef |
print the coefficients of the linear combinations. |
alpha |
significance level for CI for linear combinations of coefficients. |
Author(s)
Thomas Scheike
Examples
data(sTRACE)
# Fits Cox model
out<-cox.aalen(Surv(time,status==9)~prop(age)+prop(sex)+
prop(vf)+prop(chf)+prop(diabetes),data=sTRACE,n.sim=0)
wald.test(out,coef.null=c(1,2,3))
### test age=sex vf=chf
wald.test(out,contrast=rbind(c(1,-1,0,0,0),c(0,0,1,-1,0)))
### now same with direct specifation of estimates and variance
wald.test(coef=out$gamma,Sigma=out$var.gamma,coef.null=c(1,2,3))
wald.test(coef=out$gamma,Sigma=out$robvar.gamma,coef.null=c(1,2,3))
### test age=sex vf=chf
wald.test(coef=out$gamma,Sigma=out$var.gamma,
contrast=rbind(c(1,-1,0,0,0),c(0,0,1,-1,0)))
[Package timereg version 2.0.5 Index]