Learn R Programming

AntMAN (version 1.1.0)

AM_mix_components_prior_pois: Generate a configuration object for a Poisson prior on the number of mixture components

Description

This function generates a configuration object for a Shifted Poisson prior on the number of mixture components such that $$q_M(m)= Pr (M=m)= \frac{e^{-\Lambda}\Lambda^{m-1} }{(m-1)!} , \quad m=1,2,3,\ldots$$ The hyperparameter \(\Lambda\) can either be fixed using Lambda or assigned a \(Gamma(a,b)\) prior distribution with a and b. In AntMAN we assume the following parametrization of the Gamma density: $$p(x\mid a,b )= \frac{b^a x^{a-1}}{\Gamma(a)} \exp\{ -bx \}, \quad x>0.$$

Usage

AM_mix_components_prior_pois(a = NULL, b = NULL, Lambda = NULL, init = NULL)

Arguments

a

The shape parameter a of the \(Gamma(a,b)\) prior distribution.

b

The rate parameter b of the \(Gamma(a,b)\) prior distribution.

Lambda

It allows to set the hyperparameter \(\Lambda\) to be assigned a fixed value.

init

The initial value for \(\Lambda\), when specifying a and b.

Value

An AM_mix_components_prior object. This is a configuration list to be used as mix_components_prior argument for AM_mcmc_fit.

Details

If no arguments are provided, the default is a prior distribution with a = 1 and b = 1.

See Also

AM_mcmc_fit

Examples

Run this code
# NOT RUN {
components_prior = AM_mix_components_prior_pois (init=3,  a=1, b=1) 

# }

Run the code above in your browser using DataLab