人流与新冠病毒新规感染人数变化率的动态关系以及疫苗的作用

The new coronavirus outbreak at the end of 2019 has caused great turmoil all over the world and has yet to be contained. Therefore, controlling the number of people infected by the new coronavirus remains a major policy goal for many countries. The purpose of this paper is to analyze the dynamic relationship between mobility and the rate of change in the number of new infections based on weekly aggregate data from 20 prefectures in Japan. In addition, the paper evaluates the effects of policies implemented in Japan to control mobility and assesses the impacts of vaccination and climate factors on the number of infections. From the analysis, we show that [1] there is a strong positive relationship between the growth rate of the number of infections and mobility in the different category of places including parks, transit stations and work places, [2] the declaration of a state of emergency has a negative impact on the rate of change in the number of newly infected people, and [3] although vaccination has no significant effect in terms of reducing the susceptible population, it did significantly reduce the relationship between mobility and the rate of change in the number of newly infected people, providing useful information regarding the implementation of economic revitalization policies when a majority of people have been vaccinated.