Exercise 12.2.1: (from Mining of Massive Datasets textbook)

(Please use the book for this problem)

Modify the training set of Fig. 12.6 so that example b also includes the word nigeria (yet remains a negative example perhaps someone telling about their trip to Nigeria). Find a weight vector that separates the positive and negative examples, using: (a) The basic training method of Section 12.2.1. (b) The Winnow method of Section 12.2.3. (c) The basic method with a variable threshold, as suggested in Section 12.2.4. (d) The Winnow method with a variable threshold, as suggested in Section 12.2.4.