panel unit root tests make absolutely no sense with T=2. You are
looking for the long run behavior of a time series, and you have two
observations on the time series. No way to do that. After all, even a
Dickey-Fuller test on a single time series implies regressing the
difference in X on the lagged level of X, and you have precisely one
observation for that regression.
Kit
Kit Baum, Boston College Economics and DIW Berlin
http://ideas.repec.org/e/pba1.html
An Introduction to Modern Econometrics Using Stata:
http://www.stata-press.com/books/imeus.html
On May 3, 2008, at 02:33 , statalist-digest wrote:
>
> I tried the levin-lin test. Unfortunately, I get an error message :
>
> . sort id year
>
> . tsset id year
> panel variable: id (strongly balanced)
> time variable: year, 2004 to 2005
>
> . levinlin csp, lags(1)
>
> Levin-Lin-Chu test for csp Deterministics chosen: constant
> Reducing Andrews truncation
> no observations
> r(2000);
>
> . describe csp
>
> storage display value
> variable name type format label variable label
> -
> ----------------------------------------------------------------------
> ---------
> csp float %9.0g CSP
>
> Do you have any idea what the problem could be?
>
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
Privileged, confidential or patient identifiable information may be contained in this message. This information is meant only for the use of the intended recipients. If you are not the intended recipient, or if the message has been addressed to you in error, do not read, disclose, reproduce, distribute, disseminate or otherwise use this transmission. Instead, please notify the sender by reply e-mail, and then destroy all copies of the message and any attachments.
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
