Date: Wed, 16 Jan 2008 09:41:27 -0800
Reply-To: Dale McLerran <stringplayer_2@YAHOO.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Dale McLerran <stringplayer_2@YAHOO.COM>
Subject: Re: PROC MODEL GMM - Again
In-Reply-To: <1200477859.478dd6a3b3e8b@gold6.portugalmail.pt>
Content-Type: text/plain; charset=iso-8859-1
--- SUBSCRIBE SAS-L Filipa <filipa.fig@PORTUGALMAIL.PT> wrote:
> Hi,
> I apologise for the insistence, but I don't know how to solve my
> problem.
> I have a cross section data set and I need to estimate a linear
> regression. I estimated it with the OLS method and I verified that
> there is heteroscedasticity. To solve the heterocedasticity problem I
> estimated the model using the gmm method, but the output didn't
> present the pvalues because the model was singular. What can I do?
> Can you help me?
> Best Regards
> Filipa
>
I think you need to give more information. Tell us something about
the study, how data were collected, what variables were collected,
how those variables were collected, how you determined that there
was a heterscedasticity problem, etc. Then show the model that
you attempted to fit and also show whatever results/error messages
were returned when you attempted to fit this model.
Dale
---------------------------------------
Dale McLerran
Fred Hutchinson Cancer Research Center
mailto: dmclerra@NO_SPAMfhcrc.org
Ph: (206) 667-2926
Fax: (206) 667-5977
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