Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at statalist.org.
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
st: Regression Equation for Zero inflated negative binomial
From 
 
rachel grant <[email protected]> 
To 
 
[email protected] 
Subject 
 
st: Regression Equation for Zero inflated negative binomial 
Date 
 
Mon, 19 Sep 2011 09:54:29 +0100 
Thank you for your help. Maybe I need to explain the problem more clearly
I have used Zero Inflated negative binomial regression in Stata to
model some overdispersed, zero inflated count data. I got very nice
results and also used the postestimation tools to predict Y values.
This is included in my PhD thesis which I am about to submit. My PhD
supervisor said as well as presenting the results (i.e cofficients, p
values etc.) I also have to show "the model". I think by this he means
the regression equation in the form:
natural log (Y) = B0+B1X1 + B2X2..............
I cannot find out what the equation is for ZINB models and also I
cannot find out how to make Stata display this model.
I could just add in the coefficients myself BUT I am not sure of the
exact formula of the model for ZINB (especially the ZI part) as I
think it may be more complicated than the simple Poisson
log e  (Y) = β0 + β1Χ1 + β2Χ2 ...
I have searched everywhere to find a general equation for ZINB with no
luck and also read all the Stata help files.
I am very confused about why this seemingly simple thing should prove
so impossible! I am a beginner with stata, and previously only used
simple linear regression so thank you for your patience.
-- 
regards, Rachel Grant
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/