Simulate Negative Binomial Variates

Description

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

Usage

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

Arguments

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

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

Results

R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(MASS)
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/MASS/rnegbin.Rd_%03d_medium.png", width=480, height=480)
> ### Name: rnegbin
> ### Title: Simulate Negative Binomial Variates
> ### Aliases: rnegbin
> ### Keywords: distribution
> 
> ### ** Examples
> 
> # Negative Binomials with means fitted(fm) and theta = 4.5
> fm <- glm.nb(Days ~ ., data = quine)
> dummy <- rnegbin(fitted(fm), theta = 4.5)
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>