MIXZIP 1.0 for Mixed-effects Zero-Inflated Poisson (ZIP) Regression
mixzip1.exe (816 KB)

MIXZIP provides the maximum marginal likelihood estimates of mixed-effects Zero-Inflated Poisson (ZIP) regression models. In the context of a regression model, the ZIP model allows one to estimate one set of regression coefficients for use or non-use of services and a separate set of regression coefficients for the amount of services used, conditional on their use. The mixed-effects case is a generalization of the ZIP model for analysis of longitudinal and / or clustered service utilization data where the data within clusters are assumed to be dependent. MIXZIP uses marginal maximum likelihood estimation, utilizing a Newton-Raphson iterative solution. Currently, the program allows for single but separate random effects for both logistic and Poisson components of the model.

Authors list:
Kwan Hur, Robert D. Gibbons and Kush Kapur
Graphical user interface by Dave Patterson
1. Please fill in your name and e-mail address.
  By providing this information you are consenting to be the potential recipient of an email questionnaire about the program. If you receive the questionnaire, you are under no obligation to fill it out and return it, however, your response will be appreciated.
2. Press the Download button. If prompted whether to open or save the file, choose to save it to your computer.
  Last updated August 15, 2016. Copyright © 2003-2016 Center for Health Statistics. All Rights Reserved.

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