RE: st: FW: Marginal effects for the two-part model

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Thu, 3/2/11, Michael Palmer wrote:
> There seems to be some confusion on the computation of
> marginal effects for the TPM I described as some authors
> still suggest combined marginal effects. 

That depends on what the outcome of interest is. If you 
want the unconditional outcome, for example people get
0 cost when they don't seek medical help and some positive 
cost when they do, then you need to include both parts of 
your model. However, as I understood your original question, 
you wanted the cost conditional on seeking medical help.

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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