data in55;
 input a b c d y1 y2;
 ab=a*b;
 ac=a*c;
 ad=a*d;
 bc=b*c;
 bd=b*d;
 cd=c*d;
 abc=ab*c;
 abd=ab*d;
 acd=ac*d;
 bcd=bc*d;
 abcd=abc*d;
y=y1; output; y=y2; output;
cards;
-1 -1 -1 -1  30.3  28.6
 1 -1 -1 -1  28.5  31.4
-1  1 -1 -1  24.5  25.6
 1  1 -1 -1  25.9  27.2
-1 -1  1 -1  24.8  23.4
 1 -1  1 -1  26.9  23.8
-1  1  1 -1  24.8  27.8
 1  1  1 -1  22.2  24.9
-1 -1 -1  1  31.7  33.5
 1 -1 -1  1  24.6  26.2
-1  1 -1  1  27.6  30.6
 1  1 -1  1  26.3  27.8
-1 -1  1  1  29.9  27.7
 1 -1  1  1  26.8  24.2
-1  1  1  1  26.4  24.9
 1  1  1  1  26.9  29.3
;
run;