'bn.wf and Fig. 2.4 Favero: derivation of series with stochastic trend (ST) and deterministic trend(DT).

smpl 1 1 
genr ST1=0
genr ST2=0
smpl 2 200
series ST1= 0.1+ST1(-1) +nrnd
series ST2=0.1+ST2(-1)+nrnd
series DT= 0.1*@trend +nrnd