dist.Normal.Wishart {LaplacesDemon}R Documentation

Normal-Wishart Distribution

Description

These functions provide the density and random number generation for the normal-Wishart distribution.

Usage

dnormwishart(mu, mu0, lambda, Omega, S, nu, log=FALSE) 
rnormwishart(n=1, mu0, lambda, S, nu)

Arguments

mu

This is data or parameters in the form of a vector of length k or a matrix with k columns.

mu0

This is mean vector \mu_0 with length k or matrix with k columns.

lambda

This is a positive-only scalar.

n

This is the number of random draws.

nu

This is the scalar degrees of freedom \nu.

Omega

This is a k \times k precision matrix \Omega.

S

This is the symmetric, positive-semidefinite, k \times k scale matrix \textbf{S}.

log

Logical. If log=TRUE, then the logarithm of the density is returned.

Details

The normal-Wishart distribution, or Gaussian-Wishart distribution, is a multivariate four-parameter continuous probability distribution. It is the conjugate prior of a multivariate normal distribution with unknown mean and precision matrix.

Value

dnormwishart gives the density and rnormwishart generates random deviates and returns a list with two components.

Author(s)

Statisticat, LLC. software@bayesian-inference.com

See Also

dmvnp and dwishart.

Examples

library(LaplacesDemon)
K <- 3
mu <- rnorm(K)
mu0 <- rnorm(K)
nu <- K + 1
S <- diag(K)
lambda <- runif(1) #Real scalar
Omega <- as.positive.definite(matrix(rnorm(K^2),K,K))
x <- dnormwishart(mu, mu0, lambda, Omega, S, nu, log=TRUE)
out <- rnormwishart(n=10, mu0, lambda, S, nu)
joint.density.plot(out$mu[,1], out$mu[,2], color=TRUE)

[Package LaplacesDemon version 16.1.6 Index]