We develop a framework to estimate the aggregate capital‐labor elasticity of substitution by aggregating the actions of individual plants. The aggregate elasticity reflects substitution within plants and reallocation across plants; the extent of heterogeneity in capital intensities determines their relative importance. We use micro data on the cross‐section of plants to build up to the aggregate elasticity at a point in time. Interpreting our econometric estimates through the lens of several different models, we find that the aggregate elasticity for the U.S. manufacturing sector is in the range of 0.5–0.7, and has declined slightly since 1970. We use our estimates to measure the bias of technical change and assess the decline in labor's share of income in the U.S. manufacturing sector. Mechanisms that rely on changes in the relative supply of factors, such as an acceleration of capital accumulation, cannot account for the decline.

中文翻译：

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微数据和宏技术

我们建立了一个框架，通过汇总各个工厂的行动来估算替代的总资本－劳动力弹性。总体弹性反映了植物内的替代和植物间的重新分配；资本强度的异质程度决定了它们的相对重要性。我们使用植物横截面上的微观数据来建立某个时间点的总体弹性。通过几个不同模型的解释来解释我们的计量经济学估计，我们发现美国制造业的总弹性在0.5-0.7范围内，并且自1970年以来略有下降。我们使用我们的估计来衡量技术变化的偏差。并评估美国制造业中劳动力在收入中所占份额的下降。