data glm6_16;
  do treat=1 to 3;
input y x @@;
output;
end;
cards;
57  1.39 42  1.36  60  1.38  37  1.39  54  1.35
13  1.54 29  1.58  20  1.55  15  1.59  13  1.56
18  1.45 22  1.46  13  1.48  24  1.43  38  1.44
;
proc glm;
class treat ;
model y=x treat  x*treat /ss1;
run;
proc glm;
class treat ;
model y=x treat/ss3  ;
run; quit;