2 Squared error over last week of data (unobserved)

2.1 Base model

## `summarise()` ungrouping output (override with `.groups` argument)
##  2.5%   25%   50%   75% 97.5% 
##  7145 10062 12284 15527 25591

3 Squared errors of base model over other unobserved weeks

## `summarise()` ungrouping output (override with `.groups` argument)
##  2.5%   25%   50%   75% 97.5% 
##  8091 11711 14742 19413 36754
## `summarise()` ungrouping output (override with `.groups` argument)
##  2.5%   25%   50%   75% 97.5% 
## 11426 15098 17800 21264 27847