Re: st: ZOIB procedure

[Prerna S <maruiprerna@gmail.com>]

>
> I can think of two reasons why the statistical significance differs,
> and they are all a variation on the point that they represent
> different null-hypotheses: 1) The parameters represent relative
> effects (ratios), while marginal effects represent absolute effects
> (differences). 2) The marginal effects combine the effects on all two
> or three equations of the model.
>

Maarten,  here is what I understand of the marginal effects. One can estimate

a) mfx, predict (pr) - this is the marginal effects of the proportion
b) mfx, predict (pr0) - marginal effects of the dependent variable = 0
c) mfx, predict (pr1) - marginal effects of the dependent variable = 1
d) mfx, predict (prcond) - marginal effects of the dependent variable = (0,1)

I am  interested in b) and d) so I want to be clear on whether I have
this right. So are you suggesting that of these 4 options a) is the
best route to take whereas the remaining 3 are difficult to explain?

Thanks.
Prerna
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