Re: st: RE:RE: AW: marginal effects after ssm command

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

--- On Mon, 15/2/10, Arantza Ugidos wrote:
> We do not know where the error may be. With other commands
> mfx works fine. But after ssm it does not return marginal
> effects but the estimated coefficients again. 

-mfx- looks at the default -predict- function that is 
associated with a command, which should be left behind in
e(predict). If e(predict) is empty then -mfx- looks by default
at the change in the linear prediction, which is what you 
found. Since -ssm- is a wrapper for -gllamm- the authors 
apperently did not think it would be a good idea to provide
such a predict function. Instead, they say in the help file:
"-gllamm- itself should be used to extend the model and for 
prediction and simulation using -gllapred- or -gllasim-". 
The problem is that -mfx- won't work with -gllapred-, so 
you'll probably need to derive the marginal effects yourself.

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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