The Dynamics of Dual-Job Holding and Job Mobility.

NBER Working Paper No. 4968 December 1994 JEL Nos. J22, J63 Labor Studies

This paper concerns the incidence and dynamics of dual-job holding, and its link to job mobility. The first section presents evidence on patterns of dual-job holding, changes in hours, and job mobility in the United States, based on data from the Panel Study of Income Dynamics and the Current Population Survey. Our results indicate that most workers experience dual-job holding sometime during their working lives, and that there is a great deal of movement into and out of dual-job holding. Mobility into and out of second jobs is associated with large changes in weekly and annual hours, and there is evidence that dual-job holding is prompted by constraints on hours on the main job.

The second section of the article turns to theories of dual-job holding. Much of the empirical literature on...