Causal effects of a policy change on hazard rates of a duration outcome variable are not identified from a comparison of spells before and after the policy change if there is unobserved heterogeneity in the effects and no model structure is imposed. We develop a discontinuity approach that overcomes this by considering spells that include the moment of the policy change and by exploiting variation in the moment at which different cohorts are exposed to the policy change. We prove identification of average treatment effects on hazard rates without model structure. We estimate these effects by kernel hazard regression. We use the introduction of the NDYP program for young unemployed individuals in the UK to estimate average program participation effects on the exit rate to work as well as anticipation effects.

中文翻译：

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政策不连续性和期限结果

如果在政策变更前后没有发现异质性且未施加模型结构，则无法通过比较政策变更前后的咒语来确定政策变更对持续时间结果变量的风险率的因果影响。我们开发了一种不连续性方法，通过考虑包括政策变更时刻在内的各种咒语，并利用不同人群遭受政策变更时刻的变化来克服这种情况。我们证明无需模型结构即可确定对危害率的平均治疗效果。我们通过核危害回归估算这些影响。我们使用针对英国年轻失业者的NDYP计划介绍来估计平均计划参与对工作退出率的影响以及预期效果。