st: Multinomial selection, but Selmlog/Svyselmlog not feasible

[Guido Heineck <guido.heineck@gmx.net>]

Dear all,

I want to examine the relationship between alcohol and wages. Taking 
into account that smoking and drinking are related I estimate separate 
models for smokers and nonsmokers.

My question: Assuming that selection into employment and smoking are not 
random, how can I correct for selection bias? I first thought of using 
selmlog/svyselmlog by generating a multinomial selection var (empl. 
smoker; empl. nonsmoker, not empl. smoker; not empl. nonsmoker), but 
these progs require observed values in y for only one of these 
categories/choices.

Given that I observe wages for employees irrespective of smoking 
behavior I cannot employ selmlog/svyselmlog. I'm thus somewhat stuck 
since the authors of selmlog (Bourguignon et al.) show in their recent 
J. of Economic Surveys article that the widely used procedure proposed 
by Lee may not be appropriate.

Any insights or ideas for alternatives?

Thanks in advance.

Best,
Guido

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