confusion matrix python
By definition, entry i,j in a confusion matrix is the number of observations actually in group i, but predicted to be in group j. Scikit-Learn provides a confusion_matrix function: from sklearn.metrics import confusion_matrix y_actu = [2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 2] y_pred = [0, 0, 2, 1, 0, 2, 1, 0, 2, 0, 2, 2] confusion_matrix(y_actu, y_pred) # Output # array([[3, 0, 0], # [0, 1, 2], # [2, 1, 3]], dtype=int64)