Are Cities Losing Innovation Advantages? Online Versus Face-to-Face Interactions
利用美国专利申请数据，研究发现新冠疫情导致高密度地区创新优势下降18.5%-22.9%，本地互动频率下降是主要原因，但线上交流难以持久替代城市密度在思想交流中的作用。
Abstract How did COVID-19 affect the innovation advantages of dense locations? Using data on the universe of US patent applications, we find that the density premium in the production of novel inventions declined by 18.5%–22.9% in 2020–1 relative to its pre-pandemic level. Smartphone data on local mobility suggest that the drop in the frequency of local interactions can explain a significant portion of this effect. While COVID-19 resulted in a temporary setback in the innovation advantages of dense locations, the role of urban density in facilitating the exchange and recombination of ideas is unlikely to be persistently replaced by online communication.