Random over sampling to generate new samples in the under-represented class - 3 different types = 3 different decision functions
RandomOverSampler: over-sampling by duplicating some of the original samples of the minority class
Synthetic Minority Oversampling Technique (SMOTE): generate new samples in by interpolation and will not make any distinction between easy and hard samples to be classified using the nearest neighbors rule
Kind parameter affects how border of the decision function handled
Adaptive Synthetic (ADASYN) sampling method: generating samples next to the original samples which are wrongly classified using a k-Nearest Neighbors classifier
http://contrib.scikit-learn.org/imbalanced-learn/stable/