--- On Thu, 2/7/09, Muhammad Riaz <[email protected]> wrote:
> Thank you, would you please explain what do you mean by the
> nested nature of the data.
You used -xtgee-, so that implies that you think that your
data has a nested structure. Looking at your command the
observations seem to be nested within case_no.
> One thing I would like to add at this point, in the 1st
> command the GEE is with robust error method and then
> bootstrap is applied, however in the 2nd command we can not
> combine robust with vce(bootstrap, reps(200)).
You can't combine robust with bootstrap, these are two
alternative ways of computing the standard errors. I
suppose that the -robust- in the 2nd command is just
ignored.
A good and very readable introduction to the bootstrap is
given in:
Efron, Bradley and Robert J. Tibshirani (1993) An
Introduction to the Bootstrap. Boca Raton:
Chapman & Hall/CRC.
Hope this helps,
Maarten
-----------------------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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