Bennett McCallum (2009), applying Evans and Honkapohja's (2001) results, argues that "learnability" can save New-Keynesian models from their indeterminacies. He claims the unique bounded equilibrium is learnable, and the explosive equilibria are not. However, he assumes that agents can directly...

Unexpected inflation devalues nominal government bonds. It must therefore correspond to a decline in expected future surpluses, or a rise in their discount rates, so that the real value of debt equals the present value of surpluses. I measure each component via a vector autoregression, in...

I show that a determinate, finite price level can be achieved in an economy with no monetary frictions, and no commodity standard or other explicit redemption commitment. I make one small modification to a standard cash in advance model: I reopen the security market at the end of the day. With...

In this paper we argue that financial data are a useful proving ground for macroeconomic models, and we explore the channels that link asset market data to such models. We use Hansen and Jagannathan's bounds on the mean and standard deviation of discount factors to survey several asset pricing...

Exchange rates depreciate by the difference between the domestic and foreign marginal utility growths. Exchange rates vary a lot , as much as 10% per year. However, equity premia imply that marginal utility growths vary much more, by at least 50% per year. This means that marginal utility...

The investment return is defined as the real return that results from marginally increasing investment at date r, and then reaping the extra output and decreasing investment at date t+1 to leave the production plan for other dates unchanged. This paper constructs investment returns from...

We present a consumption-based model that explains the procyclical variation of stock prices, the long-horizon predictability of excess stock returns, and the countercyclical variation of stock market volatility. Our model has an i.i.d. consumption growth driving process, and adds a slow-moving...

The new-Keynesian, Taylor-rule theory of inflation determination relies on explosive dynamics. By raising interest rates in response to inflation, the Fed induces ever-larger inflation or deflation, unless inflation jumps to one particular value on each date. However, economics does not rule out...

In standard solutions, the new-Keynesian model produces a deep recession with deflation in a liquidity trap. The model also makes unusual policy predictions: Useless government spending, technical regress, and capital destruction have large multipliers. These predictions become larger as prices...

The new-Keynesian, Taylor-rule theory of inflation determination relies on explosive dynamics. By raising interest rates in response to inflation, the Fed induces ever-larger inflation or deflation, unless inflation jumps to one particular value on each date. However, economics does not rule out...