I am building a multi class classification model using SVM to predict the grade for essays. What can I do to improve the result especially for class 1 and class 3? Their precision and recall are really bad.
Things I have done:
1. Split train:test set to 70:30
2. Oversample the training set using smote
3. Scale the feature by using StandardScaler from Scikit-Learn
4. Perform parameter tuning by using GridSearchCv from Scikit-Learn to get the best parameter