Evaluer les politiques d'emploi : un plaidoyer pour une approche structurelle

We present arguments in favor of a structural approach to the evaluation of public policies. To illustrate this point, an evaluation using a structural model is presented. The steps of the approach are : i) definition of a theoretical framework that takes into account equilibrium effects, ii) numerical solution and estimation of structural parameters on pre-reform data, iii) test of the model?s forecasts using the post-reform data, and iv) a comparison between the reform and alternative policies, and optimization of the implemented policy. In addition, to validate the causalities of the reference model, we estimated another model in which the investment behavior has been replaced by an exogenous distribution of the productivities : this reduced form, rejected by the post-reform data, then shows that the reference model is the framework "necessary". The reform has been estimated, is the reduction in payroll taxes on low wages implemented in France in 1996.