Date: Sun, 3 Feb 2008 20:00:23 -0800
Reply-To: Daniel Nordlund <res90sx5@VERIZON.NET>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Daniel Nordlund <res90sx5@VERIZON.NET>
Subject: Re: logistic regression
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> -----Original Message-----
> From: SAS(r) Discussion [mailto:SAS-L@LISTSERV.UGA.EDU] On Behalf Of Dennis
> G. Fisher, Ph.d.
> Sent: Sunday, February 03, 2008 10:50 AM
> To: SAS-L@LISTSERV.UGA.EDU
> Subject: logistic regression
> Are the "parameter estimates" that SAS prints in PROC LOGISTIC
> considered raw (reported as B's) or standardized (reported as betas)?
> Is there any option to convert whatever it prints into the other?
> Pampel (2000) says on page 32 of his book "...logistic regression
> programs do not routinely compute standardized coefficients." However,
> on page 33 he says "SAS prints standardized coefficients for logistic
> regression." However, he continues to criticize the way that SAS
> calculates these standardized coefficients because SAS uses the same
> standard deviation, 1.8138, for all variables. I have not been able to
> find this in the documentation yet. If someone knows exactly where to
> look in the documentation to clarify this, I would appreciate their
> pointing it out. I am trying to figure out how to report these
> parameter estimates correctly, whether as B's or as beta's. TIA
> Dennis Fisher
> Dennis G. Fisher, Ph.D.
> Professor and Director
> Center for Behavioral Research and Services
> California State University, Long Beach
> 1090 Atlantic Avenue
> Long Beach, California 90813
> 562-495-2330 x121
> 562-983-1421 fax
As I understand the concept, SAS reports raw coefficients. The reported coefficient for a variable is the change in log(odds) based on a one unit change (in the original scale) of the variable of interest. Out of curiosity, what is your interest in standardized coefficients?
Hope this is helpful,
Bothell, WA USA