km {event}R Documentation

Kaplan-Meier Survivor Curves

Description

km calculates the Kaplan-Meier estimates for survival.

To plot the survivor curve, use plot(); for the empirical intensity curve, use plot.intensity(); for diagnostic curves to choose a distribution to which the data might belong, use plot.dist().

Usage

km(times, censor, group=1, freq=1, cdf=FALSE)
plot.km(z, add=FALSE, xlim, ylim=c(0,1), main=NULL, xlab="Time",
        ylab=NULL, lty=NULL, ...)
plot.intensity.km(z, add=FALSE, xlab="Time", ylab="Intensity", type="l",
        lty=NULL, ...)
plot.dist.km(z)

Arguments

times Vector of times to events or a list of vectors of such times for different individuals.
censor Vector of censoring indicators corresponding to the vector of times or to the last time in each vector of a list.
group Vector indicating to which group each individual belongs.
freq Vector of frequencies for grouped data.
cdf If TRUE, calculate the cdf instead of the survivor curve.
z An object produced by km.

Value

A matrix with class, km, containing the Kaplan-Meier estimates is returned.

Author(s)

J.K. Lindsey

See Also

plot.intensity, plot.survivor

Examples

surv <- rgamma(40,2,scale=5)
cens <- rbinom(40,1,0.9)
treat <- gl(2,20)
plot(km(surv, cens, group=treat), main="",xlab="Months",
        ylab="Probability of deterioration")
plot.dist(km(surv, cens, group=treat))
plot.intensity(km(surv, cens, group=treat),ylab="Risk of deterioration")

[Package event version 1.0 Index]