Public policies targeting individuals based on need often impose disproportionate burden on communities that lack the resources to implement these policies effectively. In an elementary school setting, I examine whether community‐level interventions focusing on similar needs and providing resources to build capacity in these communities could improve outcomes by improving the effectiveness of individual‐level interventions. I find that the extended school day policy that targets lowest‐performing schools in reading in Florida significantly improved the effectiveness of the third‐grade retention policy in these schools. These complementarities were large enough to close the gap in retention effects between targeted and higher‐performing schools.

中文翻译：

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一加一总是等于二吗？检查教育干预措施的互补性

根据需要针对个人的公共政策往往会给缺乏有效实施这些政策的资源的社区带来不成比例的负担。在小学环境中，我研究了关注类似需求并提供资源以建设这些社区能力的社区干预措施是否可以通过提高个人干预措施的有效性来改善结果。我发现，针对佛罗里达州阅读成绩最低的学校的延长上课日政策显着提高了这些学校三年级保留政策的有效性。这些互补性足够大，足以缩小目标学校和表现较好学校之间的保留效应差距。