A simplified estimate of the Effective Reproduction Number $R_t$ using its relation with the doubling time and application to Italian COVID-19 data

Gianluca Bonifazi, Luca Lista, Dario Menasce, Mauro Mezzetto, Daniele Pedrini, Roberto Spighi, Antonio Zoccoli

发表信息：: The European Physical Journal Plus, 136(4), 1-14, April 11th 2021
DOI：: 10.1140/epjp/s13360-021-01339-6

英文摘要：

A simplified method to compute $R_t$, the Effective Reproduction Number, is presented. The method relates the value of $R_t$ to the estimation of the doubling time performed with a local exponential fit. The condition $R_t = 1$ corresponds to a growth rate equal to zero or equivalently an infinite doubling time. Different assumptions on the probability distribution of the generation time are considered. A simple analytical solution is presented in case the generation time follows a gamma distribution.

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