Thanks guys. I tried with the nmissing and mvpatterns, but certainly
these do not fulfill my objective. I will test the commands
recommended by Kit.
One additional comment: I saw that there is no possibility of running
xtreg together with stepwise. In these cases how can I avoid to do the
tests manually to keep-drop variables?
Thanks for your help.
2009/11/18 Kit Baum <[email protected]>:
> <>
> I'm not sure -nmissing- is the answer here, as this involves listwise deletion: any observation with a value missing in any variable in the regression will be dropped. Something like this will test for that:
>
> sysuse auto,clear
> replace turn = . if foreign & mod(_n,2)
> replace weight = . if !foreign & !mod(_n,2)
> nmissing price rep78 turn weight
>
> g ts1 = rep78+turn
> g ts2 = rep78+weight
> g ts3 = turn+weight
> g ts4 = rep78+turn+weight
> g ts5 = length+displacement+gear_ratio
> su ts*
>
> The N reported by summarize is the number of cases that would enter the regression, given these regressors.
>
> On Nov 18, 2009, at 2:33 AM, statalist-digest wrote:
>
>> I'm using windows XP and stata 9.2. I'm running some econometric
>> models and when I got the output I can see the number of observations
>> that were used in the estimation.
>> Since my database has several missing values for almost all variables
>> I would like to know if there is some command-function that allow me
>> to see which combination of variables will produce the regression with
>> the highest avaialble number of non-missing observations.
>
>
> 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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>
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