"The best predictor of current investment at the firm level is lagged investment. This lagged-investment effect is empirically more important than the cash-flow and Q effects combined. We show that the specification of investment adjustment costs proposed by Christiano, Eichenbaum and Evans...

"Some booms in housing prices are followed by busts. Others are not. In either case it is difficult to find observable fundamentals that are correlated with price movements. We develop a model consistent with these observations. Agents have heterogeneous expectations about long-run fundamentals...