Date: Thu, 18 May 2000 12:52:46 GMT
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
Subject: Re: Need some statistical advice....
Content-type: text/plain; charset=us-ascii
Start using Proc Logistic.. Check to see if the proportional odds
assumption is valid. In the SAS output you
will see a test for this. This is the case where intercept is same,
and slopes are different. If this assumption
is not met you can go to PROC CATMOD. However you may run into
problems, when using continuous
explanatory variables. It is best to convert the continuous explanatory
variables into groups such a way
that the groups do not have empty cells. My experience is that CATMOD
worked best when I converted
my continuous variables into discrete variables.
PROC GENMOD is a general method for linear models, it can do what
Logistic and CATMOD can do.
The output statistics given may be different. Version 8 some new
things, and I am still exploring it.
I suggest you read : Logic Regression Examples, by SAS Institute.
Paul Allison ( I hope I have
not made a mistake),
wrote two books : one on
Logistic Regression, and
Survival Analysis ( covers
Proportional Hazards Model).
I am not sure of the titles of
Paul Allison's books.. but they are published by
the SAS Institute (user
PROC GENMOD is in the on-line documentation for Version 8. I am
deciphering it .
Hope this helps.