南湖新闻网讯（通讯员 赵方潇 闵师）近日，我校食物经济与管理团队研究成果以“How online food delivery platforms contributed to the resilience of the urban food system in China during the COVID-19 pandemic”为题在食品安全领域学术期刊Global Food Security发表，研究探究了中国新冠肺炎疫情期间线上外卖食品配送平台如何提高食物系统韧性。
突如其来的新冠肺炎疫情及相应的防疫措施为全球食物供应系统带来了巨大挑战。在封城政策实施期间，中国绝大多数餐厅暂停营业，但仍有部分餐厅选择将传统的线下餐饮服务转为外卖和线上配送，在一定程度上满足了居民在疫情期间的食品需求。在经历新冠肺炎疫情等外部冲击时，高效的线上外卖食品配送平台通过改善食品的可得性增强了食品系统供应的韧性。
该研究基于阿里巴巴旗下饿了么平台的日度高频交易数据，采用渐进双重差分法（Staggered DID）和事件研究法（Event Study）估计新冠肺炎疫情期间封城政策和解封政策对线上外卖配送平台和餐厅绩效的影响。研究表明，在城市封锁期间，部分餐厅继续运营并提供线上食品配送。在城市解封后，平台中营业的餐厅数量及相应配送服务的数量都出现反弹，并随着时间进一步增长。事件研究法的结果表明，封城后线上食品配送业务的调整路径与解封后的调整路径不同。异质性分析的结果还显示，疫情期间的封城和解封措施对不同类型的餐厅/菜品的影响存在差异。该研究还探究了封城政策对线上食品配送可能的影响机制，并通过一系列稳健性、安慰剂检验证实了主要结论的稳健性。
该研究以线上外卖配送平台为例，首次提供了新冠肺炎疫情对外卖消费影响的微观证据，拓宽了新冠肺炎疫情对食物消费影响的研究，也为应对食物系统外部冲击提供了政策参考。该研究证明了线上外卖食品配送平台在应对意外冲击时对城市食品系统韧性的积极贡献，从全球视角来看，对于保障全球粮食供应和帮助城市应对意外冲击的政策设计具有指导意义。
经济管理学院闵师教授为论文通讯作者，经济管理学院2018级本科毕业生赵方潇为论文第二作者，与北京大学王晓兵研究员、黄季焜教授、中国农业大学全球食物经济与政策研究院（AGFEP）田旭教授、樊胜根教授、哥廷根大学Stephan von Cramon-Taubadel教授合作撰文。
审核人：李谷成
【英文摘要】
We use high-frequency data to quantify the nature and performance of online food delivery platforms during the COVID-19 pandemic in urban China, and to estimate the short- and long-term effects of lockdown and reopening measures. A staggered difference-in-differences (DID) estimation strategy and event study approach are used to identify the effects of lockdown and reopening measures on the performance of online food delivery platforms and restaurants. The results indicate that some restaurants continued to operate and offer online food delivery while lockdowns were in effect. Both the number of operating restaurants and their online food delivery services rebounded and experienced further growth after lockdowns were lifted. The adjustment path of the online food delivery business following the implementation of lockdowns differed from the adjustment path following the lifting of lockdowns. The lockdown and reopening measures did not affect all types of restaurant/cuisine equally. We also examine possible impact mechanisms of lockdown measures on online food delivery and restaurants, and conduct robustness checks to confirm the stability of the main findings. This study contributes to the existing literature by confirming the positive contribution of online food delivery to the resilience of urban food systems in response to unexpected external shocks. Our results have implications for the design of policies to guarantee food supply and help urban food systems adapt to unexpected shocks.
论文链接：https://www.sciencedirect.com/science/article/pii/S2211912422000487#cebib0010
