% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/basehaz.gbm.R
\name{basehaz.gbm}
\alias{basehaz.gbm}
\title{Baseline hazard function}
\usage{
basehaz.gbm(t, delta, f.x, t.eval = NULL, smooth = FALSE, cumulative = TRUE)
}
\arguments{
\item{t}{The survival times.}

\item{delta}{The censoring indicator.}

\item{f.x}{The predicted values of the regression model on the log hazard
scale.}

\item{t.eval}{Values at which the baseline hazard will be evaluated.}

\item{smooth}{If \code{TRUE} \code{basehaz.gbm} will smooth the estimated
baseline hazard using Friedman's super smoother \code{\link{supsmu}}.}

\item{cumulative}{If \code{TRUE} the cumulative survival function will be
computed.}
}
\value{
A vector of length equal to the length of t (or of length
  \code{t.eval} if \code{t.eval} is not \code{NULL}) containing the baseline
  hazard evaluated at t (or at \code{t.eval} if \code{t.eval} is not
 \code{NULL}). If \code{cumulative} is set to \code{TRUE} then the returned
  vector evaluates the cumulative hazard function at those values.
}
\description{
Computes the Breslow estimator of the baseline hazard function for a
proportional hazard regression model.
}
\details{
The proportional hazard model assumes h(t|x)=lambda(t)*exp(f(x)).
\code{\link{gbm}} can estimate the f(x) component via partial likelihood.
After estimating f(x), \code{basehaz.gbm} can compute the a nonparametric
estimate of lambda(t).
}
\references{
N. Breslow (1972). "Discussion of `Regression Models and
Life-Tables' by D.R. Cox," Journal of the Royal Statistical Society, Series
B, 34(2):216-217.

N. Breslow (1974). "Covariance analysis of censored survival data,"
Biometrics 30:89-99.
}
\seealso{
\code{\link[survival]{survfit}}, \code{\link{gbm}}
}
\author{
Greg Ridgeway \email{gregridgeway@gmail.com}
}
\keyword{methods}
\keyword{survival}