eMixMargDen
assumes that a multivariate mixture of normals has been fitted
via MCMC (using rnmixGibbs
). For each MCMC draw, the marginal densities
for each component in the multivariate mixture are computed on a user-supplied
grid and then averaged over draws.
eMixMargDen(grid, probdraw, compdraw)
array of grid points, grid[,i] are ordinates for ith dimension of the density
array - each row of which contains a draw of probabilities of mixture comp
list of lists of draws of mixture comp moments
an array of the same dimension as grid with density values.
This routine is a utility routine that does not check the
input arguments for proper dimensions and type. To avoid errors, call with
output from rnmixGibbs
.
length(compdraw) is number of MCMC draws. compdraw[[i]] is a list draws of mu and inv Chol root for each of mixture components. compdraw[[i]][[j]] is jth component. compdraw[[i]][[j]]$mu is mean vector; compdraw[[i]][[j]]$rooti is the UL decomp of \(\Sigma^{-1}\).
For further discussion, see Bayesian Statistics and Marketing by Rossi, Allenby and McCulloch. http://www.perossi.org/home/bsm-1