June 25, 2008
Sylvain Chabe-Ferret, « Evaluating the impact of public policies : a general framework and applications to agricultural and forest policies », Le serveur TEL (thèses-en-ligne), ID : 10670/1.ufld0z
In this PhD thesis, we describe the evaluation problemas a decision problem: a policy is evaluated by comparing the realized outcomes to the counterfactual ones that could have happened had the policy been different. We study how well the statistical potential outcome framework and the econometric simultaneous equationsmodel performat describing and encoding public policies. The econometric approach to causality is preferred because it allows the modelling of interventions as modifications. The usual treatment effect parameters are linked to the decision problems they allow to solve. New parameters, solving problems in more general models, are defined. We then take an example of the practical problem of identifying the causal effect of public policies from observed data.We study the impact of investment subsidies on the demand for labor and materials. We derive the behavior of the within estimator under different identifying assumptions. Tests are developed using a modified version of this estimator to determine whether there is an impact of the subsidies or if the observed data exhibit only selection effects. The sensitivity of evaluation results to the welfare functions used is finally investigated. We show that getting rid of developed countries agricultural policies increases aggregate welfare in Brazil whereas at the same time it decreases the welfare of the poor.