Measuring Chinese mobility behaviour during COVID-19 using geotagged social media data

COVID-19 caused widespread disruption to normal lives and human activities. In China, the mobility behaviour response to the COVID-19 pandemic at the intra-city and population group levels is largely unknown, mainly due to a lack of individual-level publicly available mobility data. Using 210 million geotagged posts from 10 million social media users, the study quantified the changes in stay-at-home and outings across amenities and groups in China during the pandemic. The users were compared to national census data to examine their representativeness. To validate the results externally, the geotagged data was performed post-stratified correction and further comparison with commonly used data sources. The findings reveal that (i) there was between 16.8% and 57.7% decrease in visits to places of work, retail and recreation sites, parks, transit stations, grocery stores, and pharmacies within one month of the outbreak; (ii) those who are young, have a bachelor’s degree or higher, and are unmarried experienced a greater decline in outings; (iii) people preferred to visit nearby locations, resulting in a 4.3% increase in visits to retail and recreational sites within a 3-kilometer radius of their homes. The data and findings could gain insight into the asymmetric impact of the pandemic on public infrastructure use and socio-demographic groups, helping design targeted policies to promote outdoor activities, stimulate economic recovery, and alleviate social inequality in vulnerable groups.