rchaz {timereg}R Documentation

Simulation of Piecewise constant hazard model (Cox).

Description

Simulates data from piecwise constant baseline hazard that can also be of Cox type. Censor data at highest value of the break points.

Usage

rchaz(cumhazard, rr, n = NULL, entry = NULL, cum.hazard = TRUE,
  cause = 1, extend = FALSE)

Arguments

cumhazard

cumulative hazard, or piece-constant rates for periods defined by first column of input.

rr

number of simulations or vector of relative risk for simuations.

n

number of simulations given as "n"

entry

delayed entry time for simuations.

cum.hazard

specifies wheter input is cumulative hazard or rates.

cause

name of cause

extend

to extend piecewise constant with constant rate. Default is average rate over time from cumulative (when TRUE), if numeric then uses given rate.

Author(s)

Thomas Scheike

Examples


rates <-  c(0,0.01,0.052,0.01,0.04)
breaks <- c(0,10,   20,  30,   40)
haz <- cbind(breaks,rates)
n <- 1000
X <- rbinom(n,1,0.5)
beta <- 0.2
rrcox <- exp(X * beta)
cumhaz <- cumsum(c(0,diff(breaks)*rates[-1]))
cumhaz <- cbind(breaks,cumhaz)

pctime <- rchaz(haz,n=1000,cum.hazard=FALSE)

par(mfrow=c(1,2))
ss <- aalen(Surv(time,status)~+1,data=pctime,robust=0)
plot(ss)
lines(cumhaz,col=2,lwd=2)

pctimecox <- rchaz(cumhaz,rrcox)
pctime <- cbind(pctime,X)
ssx <- cox.aalen(Surv(time,status)~+prop(X),data=pctimecox,robust=0)
plot(ssx)
lines(cumhaz,col=2,lwd=2)

### simulating data with hazard as real data 
data(TRACE)

par(mfrow=c(1,2))
ss <- cox.aalen(Surv(time,status==9)~+prop(vf),data=TRACE,robust=0)
par(mfrow=c(1,2))
plot(ss)
###
pctime <- rchaz(ss$cum,n=1000)
###
sss <- aalen(Surv(time,status)~+1,data=pctime,robust=0)
lines(sss$cum,col=2,lwd=2)

pctime <- rchaz(ss$cum,rrcox)
pctime <- cbind(pctime,X)
###
sss <- cox.aalen(Surv(time,status)~+prop(X),data=pctime,robust=0)
summary(sss)
plot(ss)
lines(sss$cum,col=3,lwd=3)


[Package timereg version 1.9.4 Index]