st: Trouble with margins after suest

[Benjamin Allaire <btallaire@hotmail.com>]

Hi Statalist -

I'm trying to estimate the marginal effects of a two-part model on inpatient medical expenditures using the delta method. The first part is a logit and the second part is a glm with a log link. I use the suest command to put the two sets of estimates together. The dataset is large (~3.5 mil obs). 

Every time I try to run margins, it "hangs" in that I get the following message

delimiter now ;
. margins, dydx(cobst) subpop(if cobst==1) 
>         expression( (exp(predict(equation(inpat_logit_inpat_totpay_dum))) / (1 + exp(predict(equation(inpat_logit_inpat_totpay_dum))))) * 
>                                  exp(predict(equation(inpat_glm_inpat_totpay))) 
>                            );
Warning: cannot perform check for estimable functions.

And then.... nothing. When I run this interactively, the indicator bar moves, but it's been running for over a day now and nothing (the glm and logit take about 20 min to run). Any tips on trying to get this to resolve?

Thanks,
Ben 		 	   		  
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