Knowledge that Transforms

In October 2007, France introduced an exemption on the income tax and social security contributions that applied to wages received for hours worked overtime. The goal of the policy was to increase the number of hours worked. This article shows that this reform has had no significant impact on hours worked. Conversely, it has had a positive impact on the overtime hours declared by highly qualified wage earners, who have opportunities to manipulate the overtime hours they declare in order to optimize their tax situation since the hours they work are difficult to verify.

This paper provides among the first rigorous estimates of the labor-market returns to community college certificates and diplomas, as well as estimating the returns to the more commonly-studied associate's degrees. Using administrative data from Kentucky, we estimate panel-data models that control for differences among students in pre-college earnings and educational aspirations. Associate's degrees and diplomas have quarterly earnings returns of nearly $2,400 for women and $1,500 for men, compared with much smaller returns for certificates. There is substantial heterogeneity in returns across fields of study. Degrees, diplomas, and - for women - certificates correspond with higher levels of employment.