Disparities along racial and ethnic lines persist across domains. Distinguishing among the possible sources of such disparities matters. This article introduces an absolute test for identifying prejudice in the presence of statistical discrimination. In the context of police officers deciding whether to conduct vehicle searches, the key intuition of the test is that each officer’s search decisions and search outcomes generate a point on a concave “return possibility frontier,” (RPF) whose slope equals the officer’s search cost, or personal standard of evidence for conducting a search. Variation along a RPF provides information about search costs, and a discrepancy in these costs across drivers of different races constitutes prejudice. The model and test generalize and unify the existing literature, and the test can be partially extended to the setting where officers vary in the quality of their information, or discernment. Higher discernment generates an expansion of the frontier, and a version of the test remains valid for more discerning officers. Empirically, the test finds suggestive evidence of prejudice against Hispanic drivers and of varying discernment among officers of different races and ethnicities. These results are robust to (and not well explained by) officer experience. (JEL C26, K42, J15)

中文翻译：

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种族偏见的绝对考验

种族和民族的差异在各个领域持续存在。区分这种差异的可能来源很重要。本文介绍了在存在统计歧视的情况下识别偏见的绝对测试。在警察决定是否进行车辆搜查的情况下，测试的关键直觉是每个警察的搜索决定和搜索结果会在凹的“返回可能性边界”（RPF）上产生一个点，其斜率等于警察的搜索成本，或进行搜查的个人证据标准。沿 RPF 的变化提供了有关搜索成本的信息，而不同种族司机之间这些成本的差异构成了偏见。该模型和测试概括和统一了现有的文献，并且测试可以部分扩展到军官在信息质量或辨别力方面存在差异的环境。更高的辨别力会产生边界的扩展，并且测试的一个版本对更有辨别力的军官仍然有效。根据经验，该测试发现了对西班牙裔司机的偏见的暗示性证据，以及不同种族和民族的官员之间不同的辨别力。这些结果对军官的经验是稳健的（并且不能很好地解释）。(JEL C26, K42, J15) 该测试发现了对西班牙裔司机的偏见的暗示性证据，以及不同种族和民族的官员之间不同的辨别力。这些结果对军官的经验是稳健的（并且不能很好地解释）。(JEL C26, K42, J15) 该测试发现了对西班牙裔司机的偏见的暗示性证据，以及不同种族和民族的官员之间不同的辨别力。这些结果对军官的经验是稳健的（并且不能很好地解释）。(JEL C26, K42, J15)