Related Experiment Video
Updated: Nov 21, 2025

Quantification and Whole Genome Characterization of SARS-CoV-2 RNA in Wastewater and Air Samples
Published on: June 30, 2023
Tracking of COVID-19: A new real-time estimation using the Kalman filter
Francisco Arroyo-Marioli1, Francisco Bullano1, Simas Kucinskas2
1Central Bank of Chile, Santiago, Chile.
Abstract:
We develop a new method for estimating the effective reproduction number of an infectious disease () and apply it to track the dynamics of COVID-19. The method is based on the fact that in the SIR model, is linearly related to the growth rate of the number of infected individuals. This time-varying growth rate is estimated using the Kalman filter from data on new cases. The method is easy to implement in standard statistical software, and it performs well even when the number of infected individuals is imperfectly measured, or the infection does not follow the SIR model. Our estimates of for COVID-19 for 124 countries across the world are provided in an interactive online dashboard, and they are used to assess the effectiveness of non-pharmaceutical interventions in a sample of 14 European countries.
Related Concept Videos
Kaplan-Meier Approach
Steps in Outbreak Investigation
Residuals and Least-Squares Property
If the observed data point lies above the line, the residual is positive, and the line underestimates the actual data value for y. If the observed data point lies below the line, the residual is negative, and the line overestimates the actual data value for y.
The process of fitting the best-fit...
Linear Approximation in Frequency Domain
In contrast, nonlinear systems do not inherently possess these properties. However, for small deviations around an operating point, a nonlinear system can often be approximated as linear....
Linear Approximation in Time Domain
For a simple pendulum with a mass evenly distributed along its length and the center of mass located at half the pendulum's length,...
Estimating Population Mean with Unknown Standard Deviation
William S. Gosset (1876–1937) of the...

