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. 2020 Aug 12;9(8):220. doi: 10.3390/biology9080220
CR(t) cumulative number of reported infectious symptomatic cases at time t
CU(t) cumulative number of unreported infectious symptomatic cases at time t
DR(t) daily number of reported infectious symptomatic cases at time t
f(t) time-variable fraction of asymptomatic infectious cases who become reported symptomatic infectious cases
f0 initial fraction of asymptomatic infectious cases who become reported symptomatic infectious cases
fmax second value of fraction of asymptomatic infectious cases who become reported symptomatic infectious cases
fmax2 third value of fraction of asymptomatic infectious cases who become reported symptomatic infectious cases
I(t) number of asymptomatic infectious individuals at time t
I0 asymptomatic infectious individuals at initial time t0
N time in days of application of the first public health intervention that changes the transmission rate
N2 time in days of application of the second public health intervention that changes the transmission rate
Nf time in days for application of the first public health intervention that changes the fraction of asymptomatic infectious cases that become reported symptomatic infectious cases
Nf2 time in days for application of the second public health intervention that changes the fraction of asymptomatic infectious cases that become reported symptomatic infectious cases
NP total number of parameters in the estimation algorithm
M total number of measured data used in the estimation
R(t) number of reported symptomatic infectious individuals at time t
R0 reported symptomatic infectious individuals at initial time t0
P vector of parameters under estimation (P1, P2, …, PNP)
S(t) number of individuals susceptible to infection at time t
S0 number of individuals susceptible to infection at initial time t0
t time variable, in days
t0 beginning date of the epidemic, in days
U(t) number of unreported symptomatic infectious individuals at time t
U0 unreported symptomatic infectious individuals at initial time t0
Y vector of measured data (Ym at time tm, m = 1, …, M)
Greek Symbols
1/η average time in days that the symptomatic infectious cases remain with symptoms
1/ν average time in days that the asymptomatic infectious cases remain asymptomatic
ν1 rate at which asymptomatic infectious cases become reported symptomatic infectious cases
ν2 rate at which asymptomatic infectious cases become unreported symptomatic infectious cases
μ argument of the τ(t) function
μ2 argument of the τ(t) function
μf argument of the f(t) function
μf2 argument of the f(t) function
π(Y) marginal probability density
π(Y|P) likelihood function
πposterior posterior probability density
πprior prior probability density
τ(t) time-variable transmission rate
τ0 initial amplitude of the τ(t) function
χ1 fitting parameter in the early exponential phase of the epidemy, Equation (7a)
χ2 fitting parameter in the early exponential phase of the epidemy, Equation (7a)
χ3 fitting parameter in the early exponential phase of the epidemy, Equation (7a)