DOES RAISING THE SCHOOL LEAVING AGE REDUCE TEACHER EFFORT? EVIDENCE FROM A POLICY EXPERIMENT
研究了提高义务教育离校年龄对高中教师努力的影响，发现政策导致教师病假增加约15%，意味着教学投入和学校质量下降，并指出利用此类政策变化识别教育回报的工具变量估计可能存在向下偏误。
This paper examines the effect of an increase in the compulsory school leaving age on a measure of high school teachers' effort. Differences‐in‐Differences estimates using count data methods demonstrate that the policy led to teachers increasing their hours of sickness absence by roughly 15%. This result implies that raising the compulsory school leaving age reduces teaching inputs, and hence schooling quality. A policy implication is that these laws should be coupled with measures to compensate teachers for the additional disutility. This also suggests that instrumental variable estimates of returns to education that utilize these changes for identification may be downwardly biased.