options ls=75 nodate;

data one;
   input diet y z;
   *z=10*z;
   cards;
1 48 35
1 67 44
1 78 44
1 69 51
1 53 47
2 65 40
2 49 45
2 37 37
2 75 53
2 63 42
3 79 51
3 52 41
3 63 47
3 65 47
3 67 48
4 59 53
4 50 52
4 59 52
4 42 51
4 34 43
;
run;
proc glm;
   class diet;
   model y=diet z/solution;
run;

/* for factorial effects coding */
data one;
   set one;
   diet1=(diet=1) - (diet=4);
   diet2=(diet=2) - (diet=4);
   diet3=(diet=3) - (diet=4);
run;
proc glm;
   model y=diet1-diet3 z/solution;  /* check for agreement with JMP */
run;