Appropriate Technology and Balanced Growth
研究了企业技术选择如何决定资本与劳动的长期替代弹性，发现技术前沿形状影响要素份额，且短期与长期弹性不同，长期弹性更高。对构建宏观经济模型中的CES生产函数有实用价值。
We provide a general theoretical characterization of how firm's technology choice on a technology frontier determines the long-run elasticity of substitution between capital and labor. We show that the shape of the frontier determines factor shares and the elasticity of substitution between capital and labor. If there are adjustment costs to technology choice, the short- and long-run elasticities differ, with the long-run always higher. If the technology frontier is log-linear, the production function becomes Cobb-Douglas in the long run but, consistent with empirical evidence, short-run dynamics are characterized by gross complementarity. The approach is easily implementable and yields a powerful way to introduce CES-type production functions in macroeconomic models. We provide an illustration within an estimated dynamic general equilibrium model and show that the use of our production technology provides a good match for the short- and medium-run behavior of the US labor share.