categorical: The Categorical Distribution In lcmix: Layered and chained mixture models

Description

Density and random generation functions for the categorical distribution.

Usage

 ```1 2``` ```dcategorical(x, prob, log=FALSE) rcategorical(n, prob) ```

Arguments

 `x` vector of integers between 1 and some integer K, inclusive. `prob` vector of probabilities such that `sum(prob) = 1` and `length(prob)` = K. `log` logical; if `TRUE`, density is given as the log-density. `n` number of observations.

Details

The categorical distribution is a special case of the multinomial distribution with size 1. Values may be between 1 and some integer K, inclusive. If the random variable X is categorical with probability vector p of length K, then P(X=x) = p_x. The density is

f(x) = prod_k p_k^I(x=k) = p_x

where I(.) is the indicator function and k = 1,…,K.

Value

`dcategorical` gives the density and `rcategorical` generates random deviates.

Author(s)

Daniel Dvorkin

`Multinom` in package `stats`.