Before revision:  GIR translates residual covariance information into adjusted alphas and nests alphas and Information Ratio as special cases . Simulation results show that GIR is robust to  model misspecification and produces stable out-of-sample returns.
After revision:  GIR translates residual covariance information into adjusted alphas and nests alphas and Information Ratio as special cases , depending on the amount of information used in the residual covariance matrix. We show that GIR is robust to model misspecification and produces stable out-of-sample returns.