1. Compute the new weights for all the terms in document DOC4 using the tf x idf approach.
2. Compute the new weights for all the terms in documents DOC4 using the signal-to-noise ratio approach.
3. Using the Keyword Discrimination approach, determine if Term4 is a good index term or not (by computing it's discriminant). To compute average similarities use Cosine similarity as your similarity measure. Show your work.