% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/bivariate_laplace_residual.R
\name{biv_hazard_gradient}
\alias{biv_hazard_gradient}
\title{Bivariate Hazard Gradient}
\usage{
biv_hazard_gradient(
  t1,
  t2,
  surv_fn = NULL,
  k1 = 1,
  k2 = 1,
  theta = 0,
  eps = 1e-07
)
}
\arguments{
\item{t1, t2}{Evaluation points (non-negative).}

\item{surv_fn}{A function \code{function(x1, x2)} returning the joint
survival probability.  Defaults to Gumbel bivariate exponential.}

\item{k1, k2, theta}{Parameters for the default Gumbel distribution.}

\item{eps}{Step size for numerical differentiation (default \code{1e-7}).}
}
\value{
A named numeric vector \code{(h1, h2)}.
}
\description{
Computes the bivariate hazard gradient
\deqn{h_i(t_1,t_2) = -\frac{\partial}{\partial t_i}\log\bar{F}(t_1,t_2),
  \quad i = 1, 2.}
}
\examples{
biv_hazard_gradient(t1 = 1, t2 = 1)
biv_hazard_gradient(t1 = 0.5, t2 = 0.5, k1 = 2, k2 = 1.5, theta = 0.3)

}
\references{
Jayalekshmi S., Rajesh G., Nair N.U. (2022).
\doi{10.1080/03610926.2022.2085874}
}
