Before revision:  SUIR model adds a unique U (Undiagnosed) state of the epidemic and divides the population into four states: S (Susceptible), U (Undiagnosed), I (Infectious and Uninfectious), and R (Recovered).
After revision:  Our model is a modified susceptible-infected-recovered (SIR) model that injects undiagnosed state and offers pre-training effective reproduction number. Our SUIR model is more precise than the traditional SIR model. Moreover, we combine domain knowledge of the epidemic and divides the population into four states: S (Susceptible), U (Undiagnosed), I (Infectious and Uninfectious), and R (Recovered).