<>
Martin said
" so it is not telling you anything for which you need to estimate the
regression to find out."
So the point estimate is equal to ouput of other commands, bout how
about
the CI?
The unconditional CI is larger:
. means mpg
Variable | Type Obs Mean [95% Conf.
Interval]
-------------+----------------------------------------------------------
mpg | Arithmetic 74 21.2973 19.9569
22.63769
| Geometric 74 20.58444 19.38034
21.86335
| Harmonic 74 19.92318 18.81185
21.17405
------------------------------------------------------------------------
because the standardized regressors that are added to the model are
indeed correlated with mpg:
_cons | 21.2973 .4121741 51.67 0.000 20.47524
22.11935
but as you can see that doesn't make much difference in testing any
meaningful hypothesis about the mean of mpg.
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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