Question: What type of lexical, syntactic, semantic and polarity features are used?
Answer: Our lexical features include 1-, 2-, and 3-grams in both word and character levels., number of characters and the number of words, POS tags, 300-dimensional pre-trained word embeddings from GloVe, latent semantic indexing, tweet representation by applying the Brown clustering algorithm, positive words (e.g., love), negative words (e.g., awful), positive emoji icon and negative emoji icon, boolean features that check whether or not a negation word is in a tweet