Air pollution in urban centers has become a key public concern around the world. Apart from its adverse health effects, air pollution could impact less visible outcomes like cognitive performance. Standardized tests are a fixture of all education settings that are susceptible to pollution shocks because they require high cognitive function. Given that test scores are widely used as signals by parents, employers, and education institutions, pollution shocks could render tests unfair and unreliable. In this paper, we combine pollution data with test scores from a large testing institution in Iran between 2012 and 2017 to quantify the impact of short-term exposure to air pollution on test performance. We use visibility as an instrument for exposure to PM10 and PM2.5 on the exam day in a student fixed effects specification to study the impact of PM. We find that a one standard deviation increase in PM10 and PM2.5 is respectively associated with 0.047 and 0.029 of a standard deviation decrease in test scores. The effect is larger for males and analytical subjects. The results are robust to inclusion of other pollutants and several specification checks.

中文翻译：

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短期暴露于环境空气污染对伊朗考试成绩的影响

城市中心的空气污染已成为全球公众关注的重要问题。除了对健康的不利影响外，空气污染还可能影响不太明显的结果，例如认知能力。标准化测试是所有容易受到污染冲击的教育环境的固定工具，因为它们需要高认知功能。鉴于考试成绩被家长、雇主和教育机构广泛用作信号，污染冲击可能会使考试变得不公平和不可靠。在本文中，我们将污染数据与伊朗一家大型检测机构 2012 年至 2017 年的测试分数相结合，以量化短期暴露于空气污染对测试性能的影响。我们在学生固定效应规范中使用可见性作为在考试当天暴露于 PM10 和 PM2.5 的工具来研究 PM 的影响。我们发现 PM10 和 PM2.5 增加一个标准偏差分别与测试分数标准偏差减少 0.047 和 0.029 相关。对男性和分析对象的影响更大。结果对于包含其他污染物和多项规格检查是稳健的。