workfile ma2 u 1 300
series e = 0
series ma21=0
series ma22=0
series ma23=0
series ma24=0
series ma41=0
smpl 1 300
rndseed 123456789
series e = nrnd
ma21=e+0.5*e(-1)+0.4*e(-2)
ma22=e+0.5*e(-1)-0.4*e(-2)
ma23=e-0.5*e(-1)+0.4*e(-2)
ma24=e-0.5*e(-1)-0.4*e(-2)
ma41=e-0.5*e(-1)-0.4*e(-2)+0.5*e(-3)+0.4*e(-4)