Metodos Matematicos da Fisica

Residuals. Residuals are the difference between reported and predicted cases, using the last day fitted curve. There are growing oscillations in the residuals from US, Spain, Italy and Germany case data. Iran has the most regular oscillations in their residuals, as shown in Figure res-Iran. These oscillations superpose a modulation in the case data, which can not be accounted by the hyperbolic tangent in the model function. Perhaps a q-deformed hyperbolic tangent could delivery a better response, using the deformation parameter to control its steepness.