| confirmed | Confirmed COVID-19 cases | 
| death | Confirmed COVID-19 deaths | 
| eSAIR | Extended state-space SIR with a subset of the population showing antibody positivity | 
| qh.eSIR | Extended state-space SIR with quarantine | 
| recovered | Confirmed COVID-19 recovered | 
| tvt.eSIR | Fit extended state-space SIR model with time-varying transmission rates | 
| tvt.eSIR2 | Fit extended state-space SIR model with time-varying transmission rates | 
| USA_state_N | Population of US states |