* Cold3 Example;
* Build a logistic regression model for predicting 
  the probability of contracting a code based on 
  whether the subject takes ascorbic acid or not;

options linesize=70 nodate pageno=1;
data cold;
   input treatment $ cold count;
   datalines;
placebo 1  31
placebo 0 109
ascorb  1  17
ascorb  0 122
;

proc print;

proc logistic;
   class treatment;
   freq count;
   model cold (event='1') = treatment;
   output out=out p=predict lower=lower upper=upper;

proc print data=out;

run;
quit;