* SAS code for Aquatic survival data from Table 8.3;
 options linesize=70;

 data asg;
 input stage $  u  y  n @@;
 p=y/n;
 cards;
 a   0    23   25    a   0    23   25
    I other data omitted for space considerations I
 n   84    0   20    n   84   1    20

 proc standard data=asg mean=0 out=ag2;
     var u;

 proc genmod data=ag2;
  class stage;
  model y/n = u stage / dist=b link=logit type1;
  contrast 'A vs. C' stage 1 -1  0 ;
  contrast 'A vs. N' stage 1  0 -1 ;
  contrast 'C vs. N' stage 0  1 -1 ;

 run;