题目: Lumpy Innovation and the Great Twins: Great Moderation and Great Recession
主讲人：Donghai Zhang (National University of Singapore)
时间：2024年10月31日 下午14:00 – 15:30
地点：北京大学国家发展研究院 承泽园132

摘要：We document that firm-level innovation decisions are lumpy, characterized by episodes of inaction and large increases in R&D expenses. Furthermore, the share of firms making spike adjustments in their R&D expenses is pro-cyclical and explains 75% of the pro-cyclicality of aggregate R&D. Motivated by these empirical findings, we develop a medium-run business cycle model with heterogeneous innovating firms and fixed adjustment costs, featuring lumpy innovation. Through this framework, we uncover a novel mechanism underpinning the ‘Great Twins’ hypothesis: the Great Moderation–marked by diminished economic volatility up to 2008–causally intensified the severity of the subsequent Great Recession. We provide micro- and macro-level evidence supporting this hypothesis. Finally, we explore the policy implications, including a new tail-risk and variance tradeoff for central banks.

主讲人简介：Dr. Donghai Zhang is an Assistant Professor at the National University of Singapore. He earned his Ph.D. from the Universitat Pompeu Fabra in 2018. His research interests include Macroeconomics. Monetary Economics, Time Series Econometrics, and Financial Economics. Donghai's research has appeared in the Journal of Monetary Economics, the Journal of the European Economic Association, and the Economic Journal. His research has been funded by the Social Science Research Council of Singapore and the German Research Foundation