Hours Constraints Within and Between Jobs

In the empirical literature on labour supply, several models are developed to incorporate constraints on working hours. These models do not address the question to which extent working hours are constrained within and between jobs. In this paper I investigate the effect of individual changes in labour supply preferences on actual working hours. The availability of subjective information on the individual’s preferred working hours gives direct measures on the degree of adjustment of working hours within and between jobs. I take the potential endogeneity of the observed changes in labour supply preferences into account by using instrumental variables techniques. Using the Dutch Socio Economic Panel, I find for women who work in two consecutive years that the degree of adjustment of working hours within jobs is significantly smaller than between jobs. I also find that job mobility does not lead to complete adjustment in working hours, as the realized adjustment is significantly less than 100 percent of the preferred adjustment.