The Self-Sufficiency Project (SSP) was a well-known welfare-to-work experiment that provided a generous but time-limited financial incentive to leave welfare and enter the workforce. Experimental evidence showed large short-term impacts but no lasting effects. We argue that these conclusions need to be reassessed. Policy changes implemented during the SSP implied that the control group’s behavior did not provide an appropriate counterfactual. We estimate the impacts the financial incentive would have had in an unchanging policy environment. This reassessment leads to significant changes in the lessons previously reached. Our study demonstrates that experimental findings need to be interpreted with care.

中文翻译：

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在随机化后事件的存在下解释实验证据：对自给自足项目的重新评估

自给自足项目（SSP）是一项众所周知的福利到工作的实验，该实验提供了慷慨但有时间限制的财政激励措施，以使他们离开福利并进入工作队伍。实验证据表明，短期影响很大，但没有持久影响。我们认为这些结论需要重新评估。在SSP期间实施的策略更改暗示控制组的行为未提供适当的反事实。我们估计，在不断变化的政策环境中，财务激励措施将产生的影响。这种重新评估导致以前所学的课程发生了重大变化。我们的研究表明，实验结果必须谨慎解释。