Using Skipgrams, Bigrams, and Part of Speech Features for Sentiment Classification of Twitter Messages Badr Mohammed Badr author S Sameen Fatima author 2015-12 text Proceedings of the 12th International Conference on Natural Language Processing Dipti Misra Sharma editor Rajeev Sangal editor Elizabeth Sherly editor NLP Association of India Trivandrum, India conference publication badr-fatima-2015-using https://aclanthology.org/W15-5940/ 2015-12 268 275