This paper examines return predictability when the investor is uncertain about the right state variables. A novel feature of the model averaging approach used in this paper is to account for finite-sample bias of the coefficients in the predictive regressions. Drawing on an extensive...

"Agriculture on the American Great Plains has been constrained by historical water scarcity. After World War II, technological improvements made groundwater from the Ogallala aquifer available for irrigation. Comparing counties over the Ogallala with nearby similar counties, groundwater access...