st: How can I get conditional marginal effects?

[carinaxl@uvic.ca]

Hi! My model structure is as follows.

Two binary dependents variables y1 and y2 are affected by a vector of
independent variables x, but y1 and y2 are correlated. The command I use
to estimate the model is: biprobit y1 y2 x,vce(robust). Then I want to
calculate the marginal effects as follows:

marginal effects of x on y1=1 when y2=1
marginal effects of x on y1=1 when y2=0
marginal effects of x on y2=1 when y1=1
marginal effects of x on y2=1 when y1=0

I know how to get marginal effects for y1=1,y2=1,
                                       y1=1,y2=0,
                                       y2=0,y1=1,
                                       y2=0,y1=0,

But what I want to get is marginal effects for
                                       y2=1|y1=1
                                       y2=0|y1=1
                                       y1=1|y2=1
                                       y1=0|y2=1


Would you plase help me that how I can get this kind of marginal effects
in Stata? What code should I use? Thanks a lot!

Sincerely,
Carina




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