Fig. 3.

The change of the number of infected individuals in different states versus time (unit: day) with different ${\alpha }^{\prime }s$. The change of the cumulative number $C_I(t)$ of individuals in the I state for different ${\alpha }^{\prime }s$ with the estimated parameters a $\beta =0.305$, $\lambda =0.16$, b $\beta =0.3$, $\lambda =0.17$. The change of the number of individuals in the L state and A state with different ${\alpha }^{\prime }s$ at $\beta =0.3$, $\lambda =0.17$ in (c) and (d), and with the estimated parameters $\beta =0.302$, $\lambda =0.14$ when $\alpha =0.01$; $\beta =0.302$, $\lambda =0.15$ when $\alpha =0.05$; $\beta =0.307$, $\lambda =0.22$ when $\alpha =0.1$; $\beta =0.3$, $\lambda =0.17$ when $\alpha =0.2$ in (e) and (f). The data is the cumulative number of confirmed cases of Wuhan in (a) and (b). The values of other parameters are set as: ${\gamma }_1=\frac{1}{21}$, ${\gamma }_2=\frac{1}{10}$, ${\gamma }_3=\frac{1}{15}$, $\delta =0.03$, $l=0.0083$ before January 23, 2020, and $l=0$ later