Data ljm1(type = corr)。Y = beta1 f1 + beta2 f1f1 + e3,x1x1 = 1 f1f1 + 2 f1e1 + e1e1,x2x2 = aa(0.49)f1f1 + _ 2a(1.4)f1e2 + e2e2,x1x2 = 1 f1e2 + a(.E3 = err3,f1 = vf1,f1f1 = constr1,f1e1 = constr2,f1e2 = constr3,e1e1 = constr4,e2e2 = constr5,e1e2 = constr6, ......