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From | "Nick Cox" <n.j.cox@durham.ac.uk> |
To | <statalist@hsphsun2.harvard.edu> |
Subject | st: RE: URGENT HELP: Problem with xtpmg |
Date | Wed, 18 Aug 2010 18:09:37 +0100 |
On appeals of urgency etc. please see the Statalist FAQ which you were asked to read when you joined the list. "Urgency is your concern only Pleas of urgency, desperation, and the like are deprecated on Statalist. Your urgency, however compelling, is a private matter and does not translate into urgency for other members of the list. In fact, labeling your question as urgent is more likely to lead to your question being ignored by list members, who know that in most cases urgency arises from disorganization. On Statalist, the principle of charity is that you answer questions because you are able and willing to say something about the question, not because you have pity on the questioner." On repeating posts please see ditto: http://www.stata.com/support/faqs/res/statalist.html#noanswer On explaining which user-written programs you have used please see ditto: "Say what command(s) you are using. If they are not part of official Stata, say where they come from: the STB/SJ, SSC, or other archives. For more explanation, see 7. Ado-files FAQ below." The remaining question is what to say about your problem -- and about why did it got no replies when you posted it yesterday. My guess is that no one can think of anything specific and useful to say. Evidently a model which you do not specify is impossible to fit to your data. Who knows what is wrong? Perhaps the model does not suit the data, or vice versa. That is an empty comment, which is presumably why several people did not make it. To borrow a line from Maarten, try starting with a much simpler model. And please do read the FAQ. Nick n.j.cox@durham.ac.uk Anirudh Shingal I am trying to estimate a dynamic heterogeneous non-stationary panel using the pooled mean group estimator via xtpmg; in my sample N = 14 and T = 26. However, I am getting the messages "numerical derivatives are approximate Flat or discontinuous region encountered" and the log-likelihood is non-concave (even if I suppress the command, full, for getting the regression output for each N) Why is this happening? What should I do? (I would like the regression output for each N) I need this result rather urgently so any quick support would be greatly appreciated... * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/