poisson_syn {COUNT} | R Documentation |
Poisson : generic synthetic Poisson data and model
Description
poisson_syn is a generic function for developing synthetic Poisson data and a model given user defined specifications.
Usage
poisson_syn(nobs = 50000, off = 0, xv = c(1, -.5, 1))
Arguments
nobs |
number of observations in model, Default is 50000 |
off |
optional: log of offset variable |
xv |
predictor coefficient values. First argument is intercept. Use as xv = c(intercept , x1_coef, x2_coef, ...) |
Details
Create a synthetic Poisson regression model using the appropriate arguments. Offset optional. Model data with predictors indicated as a group with a period (.). See examples.
Value
py |
Poisson 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
Examples
# standard Poisson model with two predictors and intercept
sim.data <- poisson_syn(nobs = 500, xv = c(2, .75, -1.25))
mypo <- glm(py ~ . , family=poisson, data = sim.data)
summary(mypo)
confint(mypo)
# Poisson with offset and three predictors
oset <- rep(1:5, each=100, times=1)*100
loff <- log(oset)
sim.data <- poisson_syn(nobs = 500, off = loff, xv = c(1.2, -.75, .25, -1.3))
mypof <- glm(py ~ . + loff, family=poisson, data = sim.data)
summary(mypof)
confint(mypof)
# Poisson without offset, exponentiated coefficients, CI's
sim.data <- poisson_syn(nobs = 500, xv = c(2, .75, -1.25))
mypo <- glm(py ~ . , family=poisson, data = sim.data)
exp(coef(mypo))
exp(confint(mypo))
## Not run:
# default (without offset)
sim.data <- poisson_syn()
dmypo <- glm( py ~ . , family=poisson, data = sim.data)
summary(dmypo)
## End(Not run)