proc
reg
data=elec outest=out2 graphics outvif;

model y=z1-z2/ridge=0.0 to 0.1 by 0.01
0.2
0.3
0.4
0.5;

plot/ridgeplot;

proc
print
data=out2;

run;

proc
reg
data=elec outest=out3 graphics outvif;

model y=x1 x2/ridge=0.1;

proc
print
data=out3;

run;