I have been working on an email data set, and trying to predict the owner team for it. But my prediction accuracy is just 58%. I have implemented data cleansing, null value removals, duplicate removal, excluding stopwords, and then calculating tf-idf value to get my final document term matrix.
Tried various classifiers (but with default settings) but max I achieved is 58% accuracy. Might give a try to hyperparameter tuning.
Could you please give me some pointers, based on your previous experience what possibly could be going wrong? I'm simultaneously doing my own research and going through various blogs and articles.
One thought - Could it be a case of data skewness?
Your thoughts please?