st: Problem with -gdecomp- using probit

[<V.Monastiriotis@lse.ac.uk>]

Dear all,
I am trying to do a variable-specific decomposition on the results of a
probit regression. I am using the -gdecomp- command available from SSC
(ssc install gdecomp, replace). This also requires -margeff- to be
installed. For both commands I am using what I believe are the latest
versions (Version 2.2.0, 20 August 2009). 

When a run the decomposition on the probit I get the following error:
. gdecomp group: probit un hh_size foreign married schl_e age age2
= invalid name
r(198);

I get the same error message when I run -gdecomp- for a logit. But the
decomposition works fine when I run it on a linear regression (which is
however the wrong regression for my data): gdecomp group :  regress y x1
x2 

I don't think there's anything wrong with my model or the data, as the
probit estimation runs fine on its own and the -margeff- command also
works fine following the -probit- estimation. 

Any ideas as to what may be going on??!!


Thanks in advance,
Vassilis
PS: I am aware of the 'nldecompose- command, but this doesn't seem to
offer an option for a variable-specific decomposition...
===============================================
Dr Vassilis Monastiriotis
Hellenic Observatory, European Institute, LSE 
email: v.monastiriotis@lse.ac.uk 
===============================================


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