Re: st: out-of-sample prediction does not work after -regress- with lags

[maarten buis <maartenlbuis@googlemail.com>]

On Wed, May 4, 2011 at 1:24 PM, Mirko wrote:
> I cannot get out-of-sample forecasting after a regression with lags:
>
> According to the manual, "-predict- can be used to make in-sample or
> out-of-sample predictions:
> 6. predict calculates the requested statistic for all possible
> observations, whether they were used in fitting the model or not."
>
> However from the example above only one out of sample data is predicted.

To do out of sample predictions Stata must know the values of all
explanatory variables. So, in order to predict the outcome Stata needs
to know all the lagged values. If these are missing than what should it
predict? Prediction is just filling in an equation, if one of the elements
is missing than the result will be missing.

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany


http://www.maartenbuis.nl
--------------------------
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