Dear Rusers, I want to compare the different methods of variable selction in linear/logistic regression, so i want to generate simulated datasets, how to do that? e.g. response variable:y independent variables:x1-x4 residual item:e the theoretical formula is: y=2.1+0.1*x1+0.2*x2 x3,x4 are not related with y How should i do that? Thanks very much! !!SOS!! -- Kind Regards, Zhi Jie,Zhang [[alternative HTML version deleted]]