# bzip.a: The bivariate zero-inflated Poisson distribution (A) In bzinb: Bivariate Zero-Inflated Negative Binomial Model Estimator

## Description

random generation (`rbzip.a`), maximum likelihood estimation (`bzip.a`), and log-likelihood. (`lik.bzip.a`) for the bivariate zero-inflated Poisson (A) distribution with parameters equal to `(m0, m1, m2, p)`.

## Usage

 ```1 2 3 4 5``` ```lik.bzip.a(xvec, yvec, m0, m1, m2, p, param = NULL) rbzip.a(n, m0, m1, m2, p, param = NULL) bzip.a(xvec, yvec, tol = 1e-06, initial = NULL, showFlag = FALSE) ```

## Arguments

 `xvec, yvec` a pair of BZIP (A) random vectors. nonnegative integer vectors. If not integers, they will be rounded to the nearest integers. `m0, m1, m2` mean parameters of the Poisson variables. must be positive. `p` zero-inflation probability `param` a vector of parameters (`(m0, m1, m2, p)`). Either `param` or individual parameters (`m0, m1, m2, p`) need to be provided. `n` number of observations. `tol` tolerance for judging convergence. `tol = 1e-8` by default. `initial` starting value of param for EM algorithm, a vector of nine values. `showFlag` if `TRUE`, the updated parameter estimates for each iteration are printed out. If a positive integer, the updated parameter estimates for iterations greater than `showFlag` are printed out.

## Value

• `rbzip.a` gives a pair of random vectors following BZIP (A) distribution.

• `bzip.a` gives the maximum likelihood estimates of a BZIP (A) pair.

• `lik.bzip.a` gives the log-likelihood of a set of parameters for a BZIP (A) pair.

## Author(s)

Hunyong Cho, Chuwen Liu, Jinyoung Park, and Di Wu

## References

Cho, H., Liu, C., Preisser, J., and Wu, D. (In preparation), "A bivariate zero-inflated negative binomial model for identifying underlying dependence"

Li, C. S., Lu, J. C., Park, J., Kim, K., Brinkley, P. A., & Peterson, J. P. (1999). Multivariate zero-inflated Poisson models and their applications. Technometrics, 41, 29-38.

## Examples

 ```1 2 3 4 5 6 7 8``` ```# generating a pair of random vectors set.seed(1) data1 <- rbzip.a(n = 20, m0 = 1, m1 = 1, m2 = 1, p = 0.5) lik.bzip.a(xvec = data1[, 1], yvec = data1[ ,2], m0 = 1, m1 = 1, m2 = 1, p = 0.5) bzip.a(xvec = data1[,1], yvec = data1[,2], showFlag = FALSE) ```

bzinb documentation built on Dec. 8, 2019, 9:12 a.m.