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From | Sabrina Helmut <vitamint@hotmail.de> |
To | <statalist@hsphsun2.harvard.edu> |
Subject | RE: st: quasi-complete separation |
Date | Sun, 28 Aug 2011 18:01:46 +0200 |
Nick, thanks! You are right, logit works but the coefficient for the concerned variable is extremely high (48.5..) I will need an explanation for this. So, do you think my example shows quasi-complete separation which could be an explanation for the high coefficient? ---------------------------------------- > Date: Sun, 28 Aug 2011 16:43:36 +0100 > Subject: Re: st: quasi-complete separation > From: njcoxstata@gmail.com > To: statalist@hsphsun2.harvard.edu > > Sabrina, and indeed anybody else: Please do not send, or attempt to > send, attachments to Statalist. > See http://www.stata.com/support/faqs/res/statalist.html#toask where > this is explained, twice over. > > Sabrina: -logit y x- will work with this dataset, but there is only a > weak relationship. > > Nick > > On Sun, Aug 28, 2011 at 4:24 PM, Sabrina Helmut <vitamint@hotmail.de> wrote: > > I am sorry, the scatter has not been send. Thus, an example for you: > > > > binary dependent variable y > > continuous variable x > > > > y x > > 0 1 > > 0 2 > > 0 3 > > 0 4 > > 1 1 > > 1 2 > > 1 3 > > 1 4 > > 1 5 > > 1 6 > > 1 7 > > > > Thus, values of the independent variable being higher than 4 are only captured by y=1. > > So, is this a problem of quasi-complete separation? Thank you very much. > > > > > > ---------------------------------------- > >> From: vitamint@hotmail.de > >> > >> I provided a scatter for you. Am I right with the assumption that it shows the problem of quasi-complete separation? Thanks. > > * > * 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/ * * 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/