SBE-UKRI: Business Cycles, Uncertain Growth and the Distribution of Production

摘要自大衰退以来的十年里，缺乏新的商业创造和缓慢的经济增长。这个项目使用一个模型经济来探索这两种现象之间的相互作用，该模型在不同企业之间存在着巨大的差异。模型经济再现了美国经济中企业的长期规模和年龄分布，从而产生了企业的生命周期。新企业通常规模较小，并随着时间的推移而增长，因此随着初创企业的成熟，它们在经济中的地位变得更加重要。因此，初创企业数量减少对整体经济的影响随着时间的推移而增加。最初的生产和就业损失很小，但新公司的缺乏意味着长期成本远远大于最初的损失。该项目探索了可能解释长期缺乏初创企业的因素。该项目的结果将帮助研究人员和政策制定者更好地理解过去十年缓慢增长的背后原因，以及公司数量的长期减少如何导致缓慢的复苏。该项目调查了过去十年GDP和投资相对于趋势的缓慢增长，同时企业进入的数量持续减少。这项研究使用内生进入和退出的量化模型，探索了推动新业务形成大规模、长期变化的可能力量。模型经济包括在几个维度上不同的公司的分布，包括它们的年龄、生产率、资本和债务。这种分布的变化会传播外生冲击。此外，该模型还考虑到了反周期风险溢价，从而导致了公司价值的大幅变化。因此，它有可能重现与数据中的条目类似的持续减少。在这种背景下，该项目探索了持续冲击对全要素生产率增长的影响，增加了未来增长的不确定性，以及冲击对企业借贷成本的影响。模型经济作为一个实验室，通过企业进入的视角来评估缓慢的经济复苏的根源，并被用来研究这种冲击对总体经济和企业生产分布的影响。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

AbstractThe decade since the Great Recession has seen a lack of new business creation and slow economic growth. This project explores the interplay between these two phenomena using a model economy with rich differences across businesses. The model economy reproduces the long-run size and age distribution of firms in the U.S. economy and thus gives rise to a firm life cycle. New businesses are typically small and grow over time, so startups become more important in the economy as they mature. As a result, the effect on the overall economy from a decrease in the number of startups grows with time. The initial loss of production and employment is small, but the absence of new firms implies a long-term cost that is far larger than the initial loss. The project explores forces that may explain a persistent lack of startups. The results of the project will help researchers and policymakers better understand both the causes underlying the past decade of slow growth and how long-term reductions in the number of firms contribute to the slow recovery. The project investigates the slow GDP and investment growth over the past decade, relative to trend, alongside the persistent reduction in firm entry. The research explores possible forces driving large, long-lived changes in new business formation using a quantitative model with endogenous entry and exit. The model economy includes a distribution of firms that differ along several dimensions including their age, productivity, capital and debt. Changes in this distribution propagate exogenous shocks. Moreover, the model allows for countercyclical risk premia and thus large changes in firm value. As a result, it has the potential to reproduce persistent reductions in entry similar to those in the data. In this setting, the project explores the effect of persistent shocks to total factor productivity growth, increases in the uncertainty of future growth and shocks to firms’ cost of borrowing. The model economy serves as a laboratory to evaluate the sources of the slow economic recovery through the lens of firm entry, and is used to study the effect of such shocks both on the aggregate economy and on the distribution of production across firms.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.