Re: st: Probability threshold for inclusion in ZINB count model

[Nick Cox <njcoxstata@gmail.com>]

Perhaps you explain what threshold you expect there to be on relation  
to the manual entry on -zinb- or expand on how you think -zinb- should  
use such a threshold.

Nick

On 25 Feb 2012, at 05:05, Jeremy Bowling <jlbkq6@mail.missouri.edu>  
wrote:

> 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
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