As shown in Figure , low values of k, specifically k=1, led to low absolute Pearson's r (Pearson's r=0.28 for k=1). For k > 500, the correlation for EXT_PROT decreased. The highest absolute correlation between the EXT_PROT and the prototypical network performance was observed with 10<k<100 (i.e., k close to 1% of the training tasks).