中文摘要
人口规模与人均收入之间的关系长期存在争论。这些讨论中主要涉及两种相互对立的力量。一方面, 更大的人口规模意味着有限的自然资源必须在更多人之间分享。另一方面, 在其他条件相同的情况下, 更大的人口规模意味着更多的创新和更快的技术进步。我们研究了一个兼具这两种渠道的灵活模型。该模型给出了从人口到人均收入的效应符号的一个充分统计量, 该统计量取决于 (i) 全球收入中归于自然资源所有者的份额以及 (ii) 全要素生产率增长对研究投入的弹性。有关这些关键参数的现有证据——最重要的是, 支付给自然资源所有者的收入份额很小——表明, 从长期看, 人口的 (边际) 增加很可能带来人均收入的 (边际) 增加。
Abstract
The relationship between the human population size and per capita incomes has long been debated. Two competing forces feature prominently in these discussions. On the one hand, a larger population means that limited natural resources must be shared among more people. On the other hand, a larger population means more innovation and faster technological progress, other things equal. We study a flexible model that features both of these channels. This model delivers a sufficient statistic for the sign of the effect running from population to per capita income that depends on (i) the share of global income accruing to natural resource owners and (ii) the elasticity of TFP growth with respect to research inputs. Available evidence on these key parameters—most importantly, the small share of income that is paid to natural resource owners—suggests that, in the long run, (marginal) increases in population would likely lead to (marginal) increases in per capita incomes.