Fig. 25.

Comparison of curves for Umbria 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: $a_{\mathrm{f}}=-0.103(-0.116,-0.090)$, this corresponds to a half-life (in days) of 6.720(5.959, 7.704). The slope of the regression $log(\mathrm{daily}\mathrm{confirmed})\sim time$ is $a_{\mathrm{raw}}=-0.079(-0.093,-0.065)$ corresponding to a half-life (in days) of 8.810(7.478, 10.720). The slope of the regression $log(\mathrm{daily}\mathrm{tests})\sim time$ is 0.022(0.011, 0.033) corresponding to a doubling time (in days) of 32.197(21.311, 61.463). Ratio of slopes for $a_{\mathrm{f}}/a_{\mathrm{raw}}=1.311$, with corresponding half-lives’ ratio: 0.763. The slope of the regression $log(\mathrm{cumulative}\mathrm{confirmed})-log(\mathrm{cumulative}\mathrm{tested})\sim time$ is $-0.035(-0.036,-0.033)$ corresponding to a half-life (in days) of 19.892(19.118, 20.731)