中文摘要
我们研究在存在大量非正规就业的劳动力市场中，此前受限的移民获得完整且可携带的工作权利后，企业和劳动者如何调整。我们利用保加利亚和罗马尼亚于2007年加入欧盟这一事件，该事件赋予了意大利最大移民群体不受限制的工作权利。基于雇主—雇员匹配行政数据和工具变量—双重差分（IV-DID）设计，我们发现企业突然且持续地将就业构成转向EU07劳动者，压缩了本国劳动者的就业份额，但并未减少本国劳动者的雇用，也未增加其离职。我们未发现本国劳动者或EU07劳动者的工资出现任何显著变化。对于移民而言，这一零效应反映了相互抵消的构成变化：新进入统计范围的和原已在职的EU07劳动者以不同的工资轨迹进入正规劳动力队伍。与议价能力向劳动者转移相一致，EU07移民在工作流动性和工作保障方面均取得了显著改善。总体而言，证据表明取消法律限制重塑了企业的人员选择，并改变了移民的雇佣关系，改善了他们的外部选择、议价地位以及获得更稳定工作的机会。
Abstract
We study how firms and workers adjust when previously restricted migrants gain full and portable work rights in a labor market with substantial informality. We exploit the 2007 EU accession of Bulgaria and Romania, which granted unrestricted work rights to Italy's largest migrant group. Using matched employer–employee administrative data and an IV-DID design, we find that firms suddenly and persistently shift employment composition toward EU07 workers, compressing the native employment share without reducing native hiring or increasing separations. We don't detect any significant change in wages for either natives or EU07 workers. For migrants, this null effect reflects offsetting compositional shifts as newly observed and incumbent EU07 workers enter the formal workforce with different wage trajectories. Consistent with a shift in bargaining power toward workers, EU07 migrants experienced significant gains in job mobility and job security. Overall, the evidence suggests that removing legal restrictions reshaped firms’ personnel choices and altered migrants’ employment relationships, improving their outside options, bargaining position, and access to more secure jobs.