地方最低工资法、边界断点方法与政策溢出效应

中文摘要

我们使用记录劳动者工作间流动情况的地理位置精确的纵向就业数据，研究三次地方最低工资上调背景下的政策溢出效应。估计得到的工资和工时溢出影响在统计上显著、地理分布广泛，其程度足以令人担忧研究结果的解释，即使采用并非紧邻的地区作为对照组也是如此。对于幅度较小的干预，或由辖区范围较小的地方实施的干预，溢出效应似乎不那么令人担忧。如果一项政策的影响并未止于实施辖区的边界，采用边界断点方法进行因果推断可能会得出误导性结果。

Abstract

We use geographically precise longitudinal employment data documenting worker job-to-job mobility to study policy spillovers in the context of three local minimum wage increases. Estimated spillover impacts on wages and hours are statistically significant, geographically diffuse, and sufficient to create concern regarding interpretation of results even using not-immediately-adjacent regions as controls. Spillover effects appear less concerning with smaller interventions or those adopted in smaller jurisdictions. The boundary discontinuity method of causal inference may yield misleading results if a policy’s impacts do not stop at the border of the implementing jurisdiction.