Fig. 5: Model performance.
a R2 per week, overall, and by county population. b R2 per region and overall. At these coarse levels, models fit the best during April–May 2020. Fits were poor in summer and improved in some places during fall and winter, but never return to the initial high levels. c R2 as a function of the overall level of mobility, further broken down by county population. Mobility contains the most signal in the highest population counties when its overall value is extremely low. d R2 as a function of the overall level of mobility, further broken down by a wave. Mobility contains the most signal in the first wave at extremely low values. Median (solid lines) and 95% quantiles (shaded) are shown.
