Notes:  Part time is defined as usually working less than 35 hours per week on the primary job. The symbols *, **, and *** indicate that the wage penalty is significantly different from zero at the 0.10 level, 0.05 level, and 0.01 level, respectively, using heteroskedasticity-robust standard errors. Standard errors are available upon request from the authors. Regressions include controls for age (5), education (16), years (16), industry (13), occupation (10), and state (51).