Research on the impact of China's free trade zone policies on urban economic development

The paper explores the impact of China's free trade zone policies on urban economic development by way of the time-varying DID model using the annual panel data of 284 cities from 2010 to 2019. Through the study, it is found that the free trade zone policies have effectively promoted urban economic growth. Moreover, it is found that: (1) the pilot cities implementing free trade zone policies have registered economic growth via the mediating effect of foreign trade; (2) the free trade zone policies exert more obvious influential effect on eastern and coastal cities; (3) the relatively loose scope of free trade zones can more effectively promote the local urban economic development.