The paper presents a new method to solve DSGE models with a great number of heterogeneous agents. Using tools from systems and control theory, it is shown how to reduce the dimension of the state and the policy vector so that the reduced model approximates the original model with high precision....

This paper asks the question: Why has the ?general-to-specific? cointegrated VAR approach as developed in Europe had only limited success in the US as a tool for doing empirical macroeconomics, where what might be called a ?theory comes first? approach dominates? The reason this paper highlights...