Effets d'une réforme fiscale sur l'offre de travail des ménages dans un cadre collectif simulé.

The literature on household behavior contains hardly any empirical research on the within-household distributional effect of tax-benefit policies. We simulate this effect in the framework of a collective model of labor supply when shifting from a joint to an individual taxation system in France. We show that the net-of-tax relative earning potential of the wife is a significant determinant of intrahousehold negotiation but with very low elasticity. Consequently, the labor supply responses to the reform are entirely driven by the traditional substitution and income effects as in a unitary model. A sensitivity analysis shows that the distribution effect captured by the collective model is significant only for large-scale tax reform which appear to be fairly unrealistic. This result suggests however to put more effort to study the relationship between taxes, transfers and intrahousehold decision making. In particular, it seems appropriate to opt for a model slightly less general than the collective model; more structure would indeed help to characterize more precisely the way taxation can affect spouses' outside options and influence the negotiation.