This paper investigates the sensitivity of average wage gap decompositions to methods resting on different assumptions regarding endogeneity of observed characteristics, sample selection into employment, and estimators’ functional form. Applying five distinct decomposition techniques to estimate the gender wage gap in the U.S. using data from the National Longitudinal Survey of Youth 1979, we find that the magnitudes of the wage gap components are generally not stable across methods. Furthermore, the definition of the observed characteristics matters: merely including their current values (as frequently seen in wage decompositions) entails smaller explained and larger unexplained components than when including both their current values and histories in the analysis. Given the sensitivity of our results, we advise caution when using wage decompositions for policy recommendations.

中文翻译：

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关于工资差距分解的敏感性

本文研究了平均工资差距分解对基于观察特征的内生性、就业样本选择和估计函数形式的不同假设的方法的敏感性。使用 1979 年全国青年纵向调查的数据应用五种不同的分解技术来估计美国的性别工资差距，我们发现工资差距分量的大小在不同方法中通常不稳定。此外，观察到的特征的定义很重要：与在分析中同时包括当前值和历史时相比，仅包括它们的当前值（如工资分解中常见的）需要更小的解释和更大的未解释分量。鉴于我们结果的敏感性，