Table 10.

Feature Model 2 performance comparison of socioeconomic metrics versus other risk factors using linear regression.

Measure	Feature Model 2 with HDIa indicators	Feature Model 2 with population density, median age, and vaccination uptake
R2	0.763	0.661
MAEb	0.070	0.075
MSEc	0.011	0.016
RMSEd	0.107	0.128
Max error	0.265	0.312

^aHDI: Human Development Index.

^bMAE: mean absolute error.

^cMSE: mean squared error.

^dRMSE: root mean squared error.