The Regulation of Occupations and the Earnings of Women
利用人力资本模型，基于美国全国纵向调查数据，分析职业许可和职业认证对女性工资率的影响，发现持证女性时薪高出约20%，而认证无显著溢价。
In this paper, a human capital model is used to investigate the effects of occupational licensing and occupational certification on the wage rates of individual women. When we analyzed micro data available from the National Longitudinal Surveys of mature and young women, we found that licensed women earn about 20 percent more per hour after controlling for personal characteristics, regional location, human capital factors, and occupational category. No statistically significant premium was found for certified women.