We develop a simple model of the exchange rate in which agents optimize their portfolio and use different forecasting rules. They check the profitability of these rules ex post and select the more profitable one. This model produces two kinds of equilibria, a fundamental and a bubble one. In a...

In this paper we investigate the effects of central bank interventions (CBI) in a noise trading model with chartists and fundamentalists. We first estimate a model in which chartists extrapolate past returns and fundamentalists forecast a mean reverting dynamics of the exchange rate towards a...

This paper investigates the relationship between the euro-dollar exchange rate and its underlying fundamentals. First, we develop a simple theoretical model in which chartists and fundamentalists interact. This model predicts the existence of different regimes, and thus nonlinearities in the...

The target zone model of Krugman (1991) has failed empirically. In this paper, we develop a model of the exchange rate with heterogeneous agents in a free floating and a target zone regime. We show that this simple model mimics the empirical puzzles of exchange rates: excessive volatility, fat...

DSGE-models have become important tools of analysis not only in academia but increasingly in the board rooms of central banks. The success of these models has much to do with the coherence of the intellectual framework it provides. The limitations of these models come from the fact that they...

Capitalism is characterized by booms and busts. Periods of strong growth in output alternate with periods of declines in economic growth. Every macro-economic theory should attempt to explain these endemic business cycle movements. In this paper I present two paradigms that attempt to explain...