TABLE 9. Italy: Numerical Validation of the Forecast Results.

Investigated states	Infected		Deaths
Metrics	NRMSE	SMAPE	NRMSE	SMAPE
RW model (Test I)	19.05	0.36	3.515	0.145
RW model (Test II)	1.566	0.045	6.28	0.363
Proposed model (Exp.)	0.80	0.024	0.457	0.022
Proposed model (Uni.)	0.91	0.038	0.62	0.035
RW mean	2.47	0.063	0.121	0.006
RW upper bound	66.75	0.742	38.68	1.421
RW lower bound	84.197	1.545	36.279	0.714