km: Kaplan-Meier Survivor Curves

In event: Event History Procedures and Models

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)
## S3 method for class 'km'
plot(x, add=FALSE, xlim=NULL, ylim=c(0,1), 
main=NULL, xlab="Time", ylab=NULL, lty=NULL, ...)
## S3 method for class 'km'
plot.intensity(x, add=FALSE, xlab="Time", ylab="Hazard", type="l", lty=NULL, ...)
## S3 method for class 'km'
plot.dist(x, ...)

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.
x	An object produced by km.
add	Plotting control options.
main	Plotting control options.
type	Plotting control options.
ylab	Plotting control options.
xlab	Plotting control options.
xlim	Plotting control options.
ylim	Plotting control options.
lty	Plotting control options.
...	Plotting control options.

Value

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

Author(s)

J.K. Lindsey

See Also

plot.intensity, plot.surv

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")

Example output

Loading required package: rmutil

Attaching package: ‘rmutil’

The following object is masked from ‘package:stats’:

    nobs

The following objects are masked from ‘package:base’:

    as.data.frame, units

event documentation built on May 2, 2019, 4:07 a.m.