* MM HW 2.25;
data in;
 input y x1 x2 x3;
datalines;
0.22200 7.3 0.0 0.0
0.39500 8.7 0.0 0.3
0.42200 8.8 0.7 1.0
0.43700 8.1 4.0 0.2
0.42800 9.0 0.5 1.0
0.46700 8.7 1.5 2.8
0.44400 9.3 2.1 1.0
0.37800 7.6 5.1 3.4
0.49400 10.0 0.0 0.3
0.45600 8.4 3.7 4.1
0.45200 9.3 3.6 2.0
0.11200 7.7 2.8 7.1
0.43200 9.8 4.2 2.0
0.10100 7.3 2.5 6.8
0.23200 8.5 2.0 6.6
0.30600 9.5 2.5 5.0
0.09230 7.4 2.8 7.8
0.11600 7.8 2.8 7.7
0.07640 7.7 3.0 8.0
0.43900 10.3 1.7 4.2
0.09440 7.8 3.3 8.5
0.11700 7.1 3.9 6.6
0.07260 7.7 4.3 9.5
0.04120 7.4 6.0 10.9
0.25100 7.3 2.0 5.2
0.00002 7.6 7.8 20.7
;
run;
* data copied from http://zhidao.baidu.com/question/165665446.html?push=ql -- double check values;