Fig. 3.

Increases in R_t are not univocally correlated with school opening times across Italian regions.

Box plots of the indicated quantiles for the days of delay between school openings (A) and September 20–21 national election day (B) and R_t increase in Italian regions clustered by their school opening dates. Date of R_t increase was calculated as the first day of the period when median R_t started an increase sustained in time (>3 consecutives periods).