Fig. 1
From: Quantifying the spatial spillover effects of non-pharmaceutical interventions on pandemic risk
The modeling framework of SSE. A The average intensity of different NPIs for all regions by week. B The influence of NPIs on intrastate human mobility from the spatial panel model. The mobility in region i can be influenced by the NPIs in the regions i and j. Therefore, the changes in intrastate human movement \(Y_t\) can be explained by the sum of direct effects and SSE of NPIs and other effects. We use \(q_{it}\) to represent the estimated changes in intrastate human movement from the spatial panel model. C The transmission among different states of individuals. S, E, I, and A indicate susceptible, exposed, symptomatic, and asymptomatic individuals, respectively. RI and RA represent the removed symptomatic and asymptomatic individuals. \((1-q_{it})\beta _0\) indicates the transmission rate of symptomatic infected persons influenced by NPIs. a is the transmission rate of asymptomatic infected persons relative to symptomatic infected persons. Z and D denote the mean incubation period and infection period, whose inverse stand for the probability that exposed individuals become symptomatic infected individuals or that infected individuals are removed, respectively. \(\mu\) is the proportion of symptomatic patients among all infectious patients. D The average intrastate human mobility trend across regions. E The estimated weekly confirmed cases of the Washington State