sim_marg_var: Compute a Monte Carlo estimate of the marginal variances of a...

View source: R/cMVN_sampler.R

sim_marg_varR Documentation

Compute a Monte Carlo estimate of the marginal variances of a (I)GMRF

Description

Estimate marginal variances of a (I)GMRF prior defined in terms of a sparse precision matrix and possibly a set of equality constraints. The marginal variances might be used to rescale the precision matrix such that a default prior for a corresponding variance component is more appropriate.

Usage

sim_marg_var(
  D,
  Q = NULL,
  R = NULL,
  r = NULL,
  eps1 = 1e-09,
  eps2 = 1e-09,
  nSim = 100L
)

Arguments

D

factor of precision matrix Q such that Q=D'D.

Q

precision matrix.

R

equality restriction matrix.

r

rhs vector for equality constraints R'x = r, where R' denotes the transpose of R.

eps1

passed to create_cMVN_sampler.

eps2

passed to create_cMVN_sampler.

nSim

number of Monte Carlo samples used to estimate the marginal variances.

Value

A vector of Monte Carlo estimates of the marginal variances.

References

S.H. Sorbye and H. Rue (2014). Scaling intrinsic Gaussian Markov random field priors in spatial modelling. Spatial Statistics, 8, 39-51.


mcmcsae documentation built on April 12, 2025, 2:25 a.m.