any ideas about set parameters for BiasSVD to learn Netflix Prize data?

Thanks a lot. Basically, I'v tried biassgd_lambda in [1e0,1e-1,1e-2,1e-3,1e-4] and biassgd_gamma in [1e0,1e-1,1e-2,1e-3,1e-4]. But it seems does not work. And sometimes got into numerical errors at some point.
