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...

We present a simple behavioral model with chartists and fundamentalists and analyze their trading behavior in a floating regime and in a target zone regime. Regarding the floating regime the model replicates the well-known stylized facts like excessive volatility, fat tails, volatility...