Precision Recall curves for the balanced test sets (blue curves/markers) and the original unbalanced test sets (red curves/markers). Continuous lines refer to the predictions in the 0-24 h forecast horizon; open circles refer to the 24-48 h forecast horizon. The three panels refer to the three folds of the 3-fold cross-validation considered in the present study. The unbalanced dataset Prevalence is: 1.2% (year 2019), 0.9% (year 2020), and 0.9% (year 2021). All balanced datasets have a Prevalence close to 50%. All curves corresponding to all imbalanced cases (red lines/symbols) have been rescaled according to Eq. ( 8 ) to the prevalence value of the corresponding balanced cases (blue lines/symbols). The rescaled curves are in orange, dash-dotted/dotted lines. When doing that, an almost perfect superimposition between the curves is observed, confirming FlashNet’s capability to work properly in both balanced and imbalanced cases.
