The impact of citywide community quarantine policy on the urban fresh food availability: An insight from the topic clout on social media

Numerous Chinese cities implement citywide community quarantine policy (CCQP) to prevent the domestic spread of COVID-19. This kind of policy influences the food availability in the city. Our study proposed an evolutionary analysis framework that utilises the streaming data of topic clout on social media to analyse the dynamic impact of CCQP on food availability. This method contains the Mann–Whitney-U test, Mann–Kendall Trend test, and Grey Rational Analysis. We applied this method in multiple case studies to reflect fresh food availability on both the demand and supply sides. Our study revealed that, on the demand side, cereal products had the highest demand, and vegetables were the most frequently purchased; on the supply side, a rising quantity of fresh food shipment created a corresponding increase in logistics challenges. This study contributes to effectively monitoring the dynamic situation of fresh food supplied to residents throughout the implementation of the CCQP, thereby enhancing the food availability of urban residents.