tokens: The train set is used to train six classifiers , namely Logistic Regression ( LR ) , Support Vector Machine with linear kernel ( SVM ) , Linear Discriminant Analysis ( LDA ) , Random Forest ( RF ) , Decision Tree ( DT ) and KNN with ( scikit - learn 0.19.2 ( http://scikit-learn.org/stable/ ) was used to build these models with their default parameters unless stated otherwise . ) .