nb1_syn: Negative binomial (NB1): generic synthetic linear negative...

In COUNT: Functions, Data and Code for Count Data

Description

nb1_syn is a generic function for developing synthetic NB1 data and a model given user defined specifications.

Usage

nb1_syn(nobs=50000, delta=1, xv = c(1, 0.75, -1.25))

Arguments

nobs	number of observations in model, Default is 50000
delta	NB1 heterogeneity or ancillary parameter
xv	predictor coefficient values. First argument is intercept. Use as xv = c(intercept , x1_coef, x2_coef, ...)

Details

Create a synthetic linear negative binomial (NB1) regression model using the appropriate arguments. Model data with predictors indicated as a group with a period (.). See examples.

Data can be modeled using the ml.nb1.r function in the COUNT package, or by using the gamlss function in the gamlss package, using the "family=NBII" option.

Value

nb1y	Negative binomial (NB1) response; number of counts
sim.data	synthetic data set

Author(s)

Joseph M. Hilbe, Arizona State University, and Jet Propulsion Laboratory, California Institute of Technology Andrew Robinson, Universty of Melbourne, Australia.

References

Hilbe, J.M. (2011), Negative Binomial Regression, second edition, Cambridge University Press.

See Also

nb2_syn, nbc_syn

Examples

sim.data <- nb1_syn(nobs = 5000, delta = .5, xv = c(.5, 1.25, -1.5))
mynb1 <- ml.nb1(nb1y ~ . , data = sim.data)
mynb1

## Not run: 
# use gamlss to model NB1 data
library(gamlss)         
sim.data <- nb1_syn(nobs = 5000, delta = .5, xv = c(.5, 1.25, -1.5))
mynb1 <- gamlss( nb1y ~ . , family=NBII, data = sim.data)
mynb1

## End(Not run)

## Not run: 
# default
sim.data <- nb1_syn()
dnb1 <- ml.nb1(nb1y ~ . , data = sim.data)
dnb1

## End(Not run)

COUNT documentation built on May 2, 2019, 2:37 a.m.