[论文解读] Effects of the COVID-19 Pandemic on Population Mobility under Mild Policies: Causal Evidence from Sweden

Matz Dahlberg, Per‐Anders Edin+5 more|arXiv (Cornell University)|Apr 20, 2020

Urban, Neighborhood, and Segregation Studies参考文献 12被引用 43

一句话总结

该研究使用 Difference-in-Differences 设计，基于瑞典手机数据，显示温和的 COVID-19 政策导致出行显著减少，居住区域的日间居住存在感增加，社会经济群体之间效果相似。

ABSTRACT

Sweden has adopted far less restrictive social distancing policies than most countries following the COVID-19 pandemic. This paper uses data on all mobile phone users, from one major Swedish mobile phone network, to examine the impact of the Coronavirus outbreak under the Swedish mild recommendations and restrictions regime on individual mobility and if changes in geographical mobility vary over different socio-economic strata. Having access to data for January-March in both 2019 and 2020 enables the estimation of causal effects of the COVID-19 outbreak by adopting a Difference-in-Differences research design. The paper reaches four main conclusions: (i) The daytime population in residential areas increased significantly (64 percent average increase); (ii) The daytime presence in industrial and commercial areas decreased significantly (33 percent average decrease); (iii) The distance individuals move from their homes during a day was substantially reduced (38 percent decrease in the maximum distance moved and 36 percent increase in share of individuals who move less than one kilometer from home); (iv) Similar reductions in mobility were found for residents in areas with different socioeconomic and demographic characteristics. These results show that mild government policies can compel people to adopt social distancing behavior.

研究动机与目标

• 评估瑞典温和 COVID-19 政策如何影响人口流动。
• 检验流动性变化是否在社会经济和人口统计群体之间存在差异。
• 量化日间居住存在、工业/商业存在与日均出行距离的变化。
• 使用疫情前后数据，通过 Difference-in-Differences 进行因果推断。

提出的方法

• 使用瑞典一家主要运营商的手机数据来跟踪人群流动。
• 采用 Difference-in-Differences 设计，比较 2019 年 1–3 月与 2020 年 1–3 月。
• 测量日间居住区域与工业/商业区域的日间人口。
• 计算最大移动距离的变化以及移动距离小于 1 公里的比例的变化。

实验结果

研究问题

• RQ1 在温和政策下，COVID-19 疫情对日间居住区域的日间人口有什么影响？
• RQ2 工业/商业区域的日间出现度如何变化？
• RQ3 人们从家出发的旅行距离对疫情有何反应？
• RQ4 流动性变化是否在社会经济和人口统计群体之间表现出异质性？

主要发现

• 日间居住区域的人口平均增加了 64%。
• 工业/商业区域的日间出现度平均下降了 33%。
• 移动的最大距离平均下降了 38%；从家出发且移动距离小于 1 公里的比例上升了 36%。
• 在不同社会经济和人口特征的区域，流动性下降相似。