Le modèle d'équilibre général de la « Nouvelle synthèse » : quelles hypothèses retenir ?

This article has a twofold purpose. First, it describes the general-equilibrium model of the ?new synthesis,? which has rapidly become a true benchmark for macroeconomic analysis in areas such as economic-policy simulation and inflation forecasting. Second, it seeks to identify the contribution of nominal and real rigidities to the good performance of this type of model, using the marginal-likelihood criterion and the inspection of moments of order two. The main results are as follows: (1) the combination of rigid and indexed prices and rigid wages is essential to the quality of themodel?s fit to the data; (2) the only hypotheses needed are habit formation for consumption and adjustment costs for investment, the second hypothesis being crucial for reproducing real and nominal dynamics; (3) by introducing strategic complementarity, we can obtain a degree of nominal rigidity closer to that observed on macroeconomic data.