In this paper we study concentration in the European Internet upstream access market. The possibility of measuring market concentration depends on a correct definition of the market itself; however, this is not always possible, since, as it is the case of the Internet industry, very often...

Despite sound theoretical foundations a drawback of the New Keynesian model is its inability to generate adequate persistence in the variables it seeks to explain. A common solution is to modify the model to include lagged variables. However, this is unsatisfactory as many such modifications...