grizbayr (version 1.3.5)

update_dirichlet: Update Dirichlet Distribution

Description

This function updates the Dirichlet distribution with the Dirichlet-Multinomial conjugate prior update rule.

Usage

update_dirichlet(alpha_0, alpha_1, alpha_2, priors = list())

Value

tibble with columns alpha_0, alpha_1, and alpha_2

Arguments

alpha_0

Double value for alpha_0 (count of failures). Must be 0 or greater.

alpha_1

Double value for alpha_1 (count of successes side 1). Must be 0 or greater.

alpha_2

Double value for alpha_2 (count of successes side 2). Must be 0 or greater.

priors

An optional list object that contains alpha00, alpha01, and alpha02. Otherwise the function with use \(Dirichlet(1,1,1)\) as the prior distribution.

Details

TODO: This function currently only works in 3 dimensions. Should be extended into N dimensions in the future. Can use ... notation.

Examples

update_dirichlet(alpha_0 = 20, alpha_1 = 5, alpha_2 = 2)
sample_priors_list <- list(alpha00 = 2, alpha01 = 3, alpha02 = 5)
update_dirichlet(alpha_0 = 20, alpha_1 = 5, alpha_2 = 2, priors = sample_priors_list)