Nonparametric survival estimates.

## -------- pbc data
data(pbc, package="randomForestSRC")
pbc$time <- pbc$days/364.25

# This is the same as kaplan
gg_dta <- gg_survival(interval="time", censor="status",
                     data=pbc)

plot(gg_dta, error="none")

plot(gg_dta)

# Stratified on treatment variable.
gg_dta <- gg_survival(interval="time", censor="status",
                     data=pbc, by="treatment")

plot(gg_dta, error="none")

plot(gg_dta)

# ...with smaller confidence limits.
gg_dta <- gg_survival(interval="time", censor="status",
                     data=pbc, by="treatment", conf.int=.68)

plot(gg_dta, error="lines")