Re: st: ZOIB procedure

[Prerna S <maruiprerna@gmail.com>]

>
>> Both dirifit and fmlogit, moreover, do not
>> handle the sample selection problem like zoib.
>
> That depends on what you think the sample selection problem is in your
> case. In general I would not think of -zoib- as a solution for a
> sample selection problem, as that typically implies a correlation
> between the errors of the selection equation and the main equation and
> no such correlation is implied or estimated in -zoib-.
>

Indeed.  My data has a significant amount of zeros and I think they
are generated by a different process than the proportions. So it
appears that there are tradeoffs - I can either choose fmlogit to
handle the problem of multiple proportions or zoib to model the zeros
and proportions.

Thank you very much. This has been very helpful.

Prerna
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