Example 3.15 Refer to Table 3.3. There are 10 observations and the target is binary (0: do not buy laptop, 1: buy laptop). Find the entropy at the root node. Then, split the root node with age (40 years old, >40 years old) or student status (0: No, 1: Yes). Compute the information gain for both age and student status. Determine which input should be used to split the root node. Answer: Binary splitting is required here. At the root node, the entropy or information is E (R) = -0.4 (log,0.4 ) - 0.6 (log,0.6 ) = 0.9710 bits. Next, when the root node is split with age (5 observations with age