rnegbin: Simulate Negative Binomial Variates

Description Usage Arguments Details Value Side Effects Examples

View source: R/negbin.R

Description

Function to generate random outcomes from a Negative Binomial distribution, with mean mu and variance mu + mu^2/theta.

Usage

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rnegbin(n, mu = n, theta = stop("'theta' must be specified"))

Arguments

n

If a scalar, the number of sample values required. If a vector, length(n) is the number required and n is used as the mean vector if mu is not specified.

mu

The vector of means. Short vectors are recycled.

theta

Vector of values of the theta parameter. Short vectors are recycled.

Details

The function uses the representation of the Negative Binomial distribution as a continuous mixture of Poisson distributions with Gamma distributed means. Unlike rnbinom the index can be arbitrary.

Value

Vector of random Negative Binomial variate values.

Side Effects

Changes .Random.seed in the usual way.

Examples

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# Negative Binomials with means fitted(fm) and theta = 4.5
fm <- glm.nb(Days ~ ., data = quine)
dummy <- rnegbin(fitted(fm), theta = 4.5)

Example output



MASS documentation built on May 3, 2021, 5:08 p.m.

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