Labour Supply: the Roles of Human Capital and the Extensive Margin*

We specify and estimate a life-cycle labour supply model that expands on earlier work by simultaneously including human capital accumulation, saving and bequests, an active extensive margin, a realistic specification of the progressive tax structure and the Social Security system, and an accounting for private pensions and health expenditures. By incorporating all these features, we develop new insights into how taxes affect life-cycle labour supply. For instance, we find that labour supply elasticities vary in important ways with age, education and the tax structure itself. We also show how human capital affects elasticities differently on the intensive versus extensive margins.