This function returns the hessian, i.e., the matrix of
second derivatives of the log likelihood with respect to the
argument x
.
mig_loglik_hessian(x, beta, xi, Omega)
a d
by d
matrix of second derivatives if x
has length d
,
else an n
by d
by d
array if x
is an n
by d
matrix
n
by d
matrix of quantiles
d
vector \(\boldsymbol{\beta}\) defining the half-space through \(\boldsymbol{\beta}^{\top}\boldsymbol{\xi}>0\)
d
vector of location parameters \(\boldsymbol{\xi}\), giving the expected value
d
by d
positive definite scale matrix \(\boldsymbol{\Omega}\)