The Elasticity of Intergenerational Substitution, Parental Altruism, and Fertility Choice
定义了代际替代弹性（EGS），并将其与跨期替代弹性（EIS）区分开，通过校准模型发现EGS显著大于1，而EIS最多为1，识别关键在于匹配美国实际生育率。
Abstract Dynastic models common in macroeconomics use a single parameter to control the willingness of individuals to substitute consumption both intertemporally, or across periods, and intergenerationally, or across parents and their children. This article defines the concept of elasticity of intergenerational substitution (EGS), and extends a standard dynastic model in order to disentangle the EGS from the EIS, or elasticity of intertemporal substitution. A calibrated version of the model lends strong support to the notion that the EGS is significantly larger than one. In contrast, estimates of the EIS suggests that it is at most one. What disciplines the identification is the need to match empirically plausible fertility rates for the U.S. We illustrate the potential role of the EGS in macroeconomics.