Date:         Fri, 7 Nov 2008 02:02:56 -0800
Reply-To:     "cat.." <cat.b41@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         "cat.." <cat.b41@GMAIL.COM>
Organization: http://groups.google.com
Subject:      Stepwise selection in proc logistic
Comments: To: sas-l@uga.edu
Content-Type: text/plain; charset=ISO-8859-1

Dear SAS-Lers,

I'm trying to understand in detail, step by step, how the stepwise
selection process works and I study the following SAS example:

http://www.technion.ac.il/docs/sas/stat/chap39/sect44.htm

But I'm confused about one thing: The first set of covariates is: cell
smear infil li blast temp.

At step 0, only the intercept is entered, and, before entering the
step 1, a table is displayed that shows the analysis of effects
eligible for entry. Which includes, at step 0: cell smear infil li
blast temp.

Is this table supposed to display the Chi-square score of significance
of the estimate of each effect when fitting the model remis = cell
smear infil li blast temp ?

In that case, why does the code

proc logistic data=Remission descending outest=betas covout;
  model remiss=cell smear infil li blast temp;
run;

yield chi-square scores that are completely different !!

Thanks for your help.

Cheers,

Catherine.