1. Suppose that a list contains the values 20 44 48 55 62 66 74 88 93 99 at index positions 0 through 9. Trace the values of the variables….

## Compute the information gain of the term “elections” according to Eq. 5.7.

Consider the term “elections” which is present in only 50 documents in a corpus of 1000 documents. Furthermore, assume that the corpus contains 100 documents belonging to the Politics category, and 900 documents belonging to the Not-Politics category. The term “election” is contained in 25 documents belonging to the Politics category. (a) Compute the unnormalized Gini index and the normalized Gini index Gn(·) of the term “elections.” (b) Compute the entropy of the class distribution with respect to the entire data set. (c) Compute the conditional entropy of the class distribution with respect to the term “elections.” (d) Compute the mutual information of the term “elections” according to Eq. 5.6. How are your answers to (b), (c), and (d) related? (e) Compute the information gain of the term “elections” according to Eq. 5.7. How are your answers to (d) and (e) related?