<>
Martin suggested 
margeff, at(mean) 
but why not calculate the AMEs? That's why one uses margeff, after all.
Or--
logit foreign price weight length
margins, dydx(_all) post
mat b = e(b)
mat V = e(V)
which will do the same thing as just plain -margeff- (Bartus, SSC).
Kit Baum   |   Boston College Economics & DIW Berlin   |   http://ideas.repec.org/e/pba1.html
                              An Introduction to Stata Programming  |   http://www.stata-press.com/books/isp.html
   An Introduction to Modern Econometrics Using Stata  |   http://www.stata-press.com/books/imeus.html
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