How large are the aggregate productivity losses from the misallocation of resources across firms? With endogenous selection, microfrictions can induce extensive margin misallocation among firms: too many unproductive firms are active (Zombies), and too many productive firms are inactive (Shadows). Therefore, the same set of measured distortions potentially induces much larger aggregate productivity losses, as the composition of firms is shifted toward unproductive active firms. I develop and calibrate a model with plant-level microdata for Indonesia to quantify aggregate welfare in the presence of extensive margin misallocation. My estimates show that selection can magnify aggregate TFP losses from microdistortions by over 40 percent compared to existing estimates. Realistic values of measurement error even increase the relative importance of extensive margin misallocation. (JEL D22, D24, E23, J24, J31, O14, O15)

中文翻译：

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微观层次错配与选择

企业间资源错配造成的总生产力损失有多大？通过内生选择，微摩擦会导致企业间广泛的边际错配：过多的非生产性企业是活跃的（僵尸），而过多的生产性企业是不活跃的（阴影）。因此，随着企业的构成向非生产性活跃企业转移，同一组测量的扭曲可能会导致更大的总生产率损失。我为印度尼西亚开发和校准了一个带有工厂级微观数据的模型，以在存在广泛的边际分配不当的情况下量化总体福利。我的估计表明，与现有估计相比，选择可以将微失真造成的总 TFP 损失放大 40% 以上。测量误差的实际值甚至增加了广泛的边际错配的相对重要性。（JEL D22、D24、E23、J24、J31、O14、O15）