st: Probability threshold for inclusion in ZINB count model

[Jeremy Bowling <jlbkq6@mail.missouri.edu>]

I am having a hard time finding the probability threshold that zinb uses to 
include/limit observations in the count model.  Is there a set probability 
threshold?  If not how do I find the threshold?

After running zinb for a number of count models, I was seeking to run a 
simple logit model by dichotomizing my dv instead of having a count.  I 
would like to limit my observations by excluding those that would be in the 
certain zero group.  Of course the significance of the logit coefficients 
would be affected by the threshold I set (which observations are included). 
I would like to use the logit model to seek not what causes multiple 
occurrences (count) but what factors lead to the likelihood of an 
occurrence, from zero to one, for those observations not in the certain zero 
group.

If there is not a set probability threshold or it can not be found, what 
would be the best probability to use?  50% cutoff? Mean probability cutoff?

Thank you for any help! 


*
*   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/