# conduct backward stepwise variable elimination for zero inflated count regression

### Description

conduct backward stepwise variable elimination for zero inflated count regression from zeroinfl function

### Usage

1 2 |

### Arguments

`object` |
an object from function zeroinfl |

`data` |
argument controlling formula processing
via |

`dist` |
one of the distributions in zeroinfl function |

`alpha` |
significance level of variable elimination |

`trace` |
logical value, if TRUE, print detailed calculation results |

### Details

conduct backward stepwise variable elimination for zero inflated count regression from zeroinfl function

### Value

an object of zeroinfl with all variables having p-values less than the significance level `alpha`

### Author(s)

Zhu Wang <zwang@connecticutchildrens.org>

### References

Zhu Wang, Shuangge Ma, Ching-Yun Wang, Michael Zappitelli, Prasad Devarajan and Chirag R. Parikh (2014)
*EM for Regularized Zero Inflated Regression Models with Applications to Postoperative Morbidity after Cardiac Surgery in Children*, *Statistics in Medicine*. 33(29):5192-208.

Zhu Wang, Shuangge Ma and Ching-Yun Wang (2015) *Variable selection for zero-inflated and overdispersed data with application to health care demand in Germany*, *Biometrical Journal*. 57(5):867-84.