Table 1.

Statistical model parameters for different countries obtained by regression modelling considering the data up to 15 May, 2020.

Countries	Starting date	Model parameters
		Y0	α	β	ti	R2
India	February 15, 2020	3	483417	0.018357	145.59	0.9994
China	January 22, 2020	571	29892.41	0.152632	15.47	0.9937
Italy	February 19, 2020	3	86335.43	0.060355	42.73	0.9995
Canada	February 15, 2025	8	39323.2	0.043275	67.23	0.9995
USA	February 15, 2020	15	682228.7	0.049143	62.22	0.9992
Germany	February 15, 2021	25	64701.81	0.083874	44.59	0.9996
Japan	February 15, 2022	53	6540.975	0.074024	56.51	0.9956
Iran	February 15, 2023	2	45338.53	0.049268	42.58	0.9972

Where, Y₀: Infected population at zero day; α: Cumulative infected population at inflection point; β: Shape factor; t_i: Inflection time (days).