Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

st: RE: Things to consider when regressions don't converge


From   "de la Garza, Adrian" <ADelagarza@imf.org>
To   <statalist@hsphsun2.harvard.edu>
Subject   st: RE: Things to consider when regressions don't converge
Date   Tue, 18 May 2004 11:37:30 -0400

Jean, thanks a lot. But perhaps I should have explained myself better.
It is my -R- that I want, that is, the number of bonds issued by a
particular borrower SO FAR at each different point in time. Your -R-
would give me the FINAL total of bonds that a particular borrowed issue
throughout the whole sample and that number would be repeated for each
observation within the same borrower. This is not what I want.

And yes, I tried the twostep option and it does run my regression more
smoothly but I am not sure why it doesn't work without the twostep
option.

Thank you.
Adrian

> -----Original Message-----
> From: jean ries [mailto:ries@ires.ucl.ac.be] 
> Sent: Tuesday, May 18, 2004 11:26 AM
> To: statalist@hsphsun2.harvard.edu
> Subject: Re: Things to consider when regressions don't converge
> 
> 
> At 16:29 18/05/2004, you wrote:
> >I am running a Heckman selection model (shown below) and after this
> >non-converging story I started playing around with my equation and
> >noticed that my -lR- variable might be the one that's giving 
> me trouble.
> >-lR- is ln(R), and -R- is generated as follows:
> >
> >sort borrower indic signdate mtydate amount
> >by borrower: g R = _n
> >
> >so -R- is the number of bonds issued by a particular borrower at each
> >different point in time.
> 
> I don't think that R represents what you expect it to 
> represent. The way 
> you define it, R contains the current observation number for 
> each borrower. 
> Try the following to obtain the number of bonds issued by a 
> particular 
> borrower :
> 
> bysort borrower: g R = _N
> 
> and:
> 
> help _variables
> 
> In any case, have a look at the Stata reference manual. It 
> contains a nice 
> discussion on problems related to Heckman selection models. 
> As suggested 
> there, you should try to fit your model using the two-step method.
> 
> Hope this helps,
> 
> jean 
> 
> *
> *   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/
> 

*
*   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/



© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index