zero_nb {hurdlr} | R Documentation |
Zero-Inflated Negative Binomial Regression Model
Description
zero_nb
is used to fit zero-inflated
negative binomial regression models to count data via Bayesian inference.
Usage
zero_nb(y, x, size, a = 1, b = 1, mu.start = 1, beta.prior.mean = 0,
beta.prior.sd = 1, iters = 1000, burn = 500, nthin = 1, plots = T,
progress.bar = T)
Arguments
y |
numeric response vector. |
x |
numeric predictor matrix. |
size |
size parameter for negative binomial likelihood distributions. |
a |
shape parameter for gamma prior distributions. |
b |
rate parameter for gamma prior distributions. |
mu.start |
initial value for mu parameter. |
beta.prior.mean |
mu parameter for normal prior distributions. |
beta.prior.sd |
standard deviation for normal prior distributions. |
iters |
number of iterations for the Markov chain to run. |
burn |
numeric burn-in length. |
nthin |
numeric thinning rate. |
plots |
logical operator. |
progress.bar |
logical operator. |
Details
Fits a zero-inflated negative binomial (ZINB) model.
Value
zero_nb
returns a list which includes the items
- mu
numeric vector; posterior distribution of mu parameter
- beta
numeric matrix; posterior distributions of regression coefficients
- p
numeric vector; posterior distribution of parameter 'p', the probability of a given zero observation belonging to the model's zero component
- ll
numeric vector; posterior log-likelihood
Author(s)
Taylor Trippe <ttrippe@luc.edu>
Earvin Balderama <ebalderama@luc.edu>