mata:
T=600     //number of markets
K_S=1    //number of variables with stochastic coefficients
R=200   //number of random draws
st_matrix("T", T)
//pointers to the market specific random draws:
V=J(T,1,NULL)   //   T by 1  0 matrix

for(t=1;t<=T;t++){
V[t]=(rnormal(K_S,R,0,1)) //dimension K_S x R
}
end