One Vs One Multi Class Classification

This method is used to extend binary classifier to classify multiple classes.

  • For this one, we will train $nC2$ number of models
  • Each model will be trained on pair of classes (x, y)
    • Each model will predict if the instance is of class x or y
  • The final prediction will be the majority count of the prediction class


  1. Doesn't create Imbalanced dataset like One vs Rest or One vs All Multi Class Classification
  2. So works better with Support Vector Machine (SVM), K-nearest Neighbor (KNN) which are dependent on data