Table 3 Different stages of spatial diffusion process and scale growth process of COVID-19 in Chinese mainland.
Stages | Spatial diffusion | Periods | Scale growth | Periods |
|---|---|---|---|---|
Stage 1 | Initial stage | Before Jan 19 | Initial stage | Before Jan 19 |
Stage 2 | Rapid diffusion stage | Jan 19-26 | Acceleration stage | Jan 19–Feb 5 |
Stage 3 | Hierarchical diffusion stage | Jan 27-Feb 9 | Deceleration stage | Feb 6-14 |
Stage 4 | Contraction stage | After Feb 10 | Late stage | After Feb 14 |
