Fig. 11.

Comparison of curves for Emilia Romagna region. Left: y–axis on normal scale, right: on logarithmic scale. Regression line shown for $log(\mathrm{daily}\mathrm{confirmed})-log(\mathrm{daily}\mathrm{tested})\sim time$ with $95\%$ prediction band. Slope of regression with $95\%$ confidence interval: $a_{\mathrm{f}}=-0.050(-0.055,-0.046)$, this corresponds to a half-life (in days) of 13.774(12.594, 15.196). The slope of the regression $log(\mathrm{daily}\mathrm{confirmed})\sim time$ is $a_{\mathrm{raw}}=-0.034(-0.038,-0.029)$ corresponding to a half-life (in days) of 20.681(18.199, 23.948). The slope of the regression $log(\mathrm{daily}\mathrm{tests})\sim time$ is 0.016(0.011, 0.035) corresponding to a doubling time (in days) of 42.042(19.760, 62.087). Ratio of slopes for $a_{\mathrm{f}}/a_{\mathrm{raw}}=1.502$, with corresponding half-lives’ ratio: 0.666. The slope of the regression $log(\mathrm{cumulative}\mathrm{confirmed})-log(\mathrm{cumulative}\mathrm{tested})\sim time$ is $-0.017(-0.018,-0.016)$ corresponding to a half-life (in days) of 40.674(38.280, 43.387). The data for the dates 28th–30th March are removed for the regression analysis