Notes. Top section: confusion matrix showing the results of kNN classification (k = 15) with threshold P(BHB) > 0.5. This is the combined result of ten independent classifications with resampling of the training and testing sets. The rows show the true class (according to Xue et al.), the columns show the classifier output class. When shown as percentages, the quantities in the rows should add to 100%, but the quantities in the columns in general do not. The completeness and contamination are also shown – and the contamination is corrected for the class imbalance using the simple prior. Middle section: the same confusion matrix, with output probabilities corrected for the simple prior. Bottom section: the results with output probabilities corrected for the prior probability as function of g magnitude and galactic latitude.