CAS Exam MAS-II Fall 2018, Question 38
Study guide: Exam MAS-II
You are given the following unpruned decision tree:
The values at each terminal node are the residual sums of squares (RSS) at that node. The table below gives the RSS at nodes S, T, and X if the tree was pruned at those nodes:
| Node | RSS |
|---|---|
| S | 251 |
| T | 209 |
| X | 86 |
The RSS for the null model is 486. You use the cost complexity pruning algorithm with the tuning parameter, \alpha, equal to 9 in order to evaluate the following pruning strategies.
- I. No nodes pruned
- II. Prune node S only
- III. Prune node T only
- IV. Prune node X only
- V. Prune both nodes S and X
Determine which pruning strategy is selected.
- A) I
- B) II
- C) III
- D) IV
- E) V
Answer this question and see the worked solution