search for: pseudovariable

Displaying 1 result from an estimated 1 matches for "pseudovariable".

2012 May 03
0
Modified Cholesky decomposition for sparse matrices
I am trying to estimate a covariance matrix from the Hessian of a posterior mode. However, this Hessian is indefinite (possibly because of numerical/roundoff issues), and thus, the Cholesky decomposition does not exist. So, I want to use a modified Cholesky algorithm to estimate a Cholesky of a pseudovariance that is reasonably close to the original matrix. I know that there are R packages that