Central banks throughout the world predict inflation with new-Keynesian models where, after a shock, the unemployment rate returns to its so called "natural rate'. That assumption is called the Natural Rate Hypothesis (NRH). This paper reviews a body of work, published over the last decade,...

Existing literature continues to be unable to offer a convincing explanation for the volatility of the stochastic discount factor in real world data. Our work provides such an explanation. We do not rely on frictions, market in completeness or transactions costs of any kind. Instead, we modify a...

This paper studies the connection between the stock market and the unemployment rate. I establish three facts. First, the log of the real value of the S&P 500 and the log of a logistic transformation of the unemployment rate are non-stationary cointegrated series. Second, the stock market...

The representative agent model (RA) has dominated macroeconomics for the last thirty years. This model does a reasonably good job of explaining the co-movements of consumption, investment, GDP and employment during normal times. But it cannot easily explain movements in asset prices. Two facts...

This paper uses a model with a continuum of equilibrium steady state unemployment rates to explore the effectiveness of fiscal policy. The existence of multiple steady state equilibria is explained by the presence of search and recruiting costs. I use the model to explain the current financial...

We introduce a solution technique for the study of discrete time stochastic models populated by long-lived agents. We introduce aggregate uncertainty and complete markets into a 'perpetual-youth' model of a kind first studied by Olivier Blanchard and we show that the pure-trade version of the...

This paper is about the properties of Markov switching rational expectations (MSRE) models. We present a simple monetary policy model that switches between two regimes with known transition probabilities. The first regime, treated in isolation, has a unique determinate rational expectations...

This paper is part of a broader project that provides a microfoundation to the General Theory of J.M. Keynes. I call this project 'old Keynesian economics' to distinguish it from new-Keynesian economics, a theory that is based on the idea that to make sense of Keynes we must assume that prices...

This paper presents empirical evidence from U.S. data of a structurally stable aggregate supply relationship between real and nominal rates of interest and the rate of unemployment. The paper reviews theories of contracts that are based on the twin assumptions of asymmetric information and...

DSGE models are characterized by the presence of expectations as explanatory variables. To use these models for policy evaluation, the econometrician must estimate the parameters of expectation terms. Standard estimation methods have several drawbacks, including possible lack or weakness of...