We show that economic restrictions of cointegration between asset cash flows and aggregate consumption have important implications for return dynamics and optimal portfolio rules, particularly at long investment horizons. When cash flows and consumption share a common stochastic trend (i.e., are...

The authors investigate the small sample properties of three alternative generalized method of moments estimators of asset pricing models. The estimators that they consider include ones in which the weighting matrix is iterated to convergence and ones in which the weighting matrix is changed...