III. Computation (points per item vary). You may use your calculator or spreadsheet software. For items involving computations, you may earn partial credit when the final answer is incorrect if it is evident from what you have written on the exam that you recognized the correct strategy but failed in the implementation. Only work that is written on the exam and legible can be considered for partial credit. If you would like to submit a spreadsheet to support your answer, please upload it along with your exam and reference it in the appropriate section.

26. (10 points) A company that sells posters of cartoons from the 1980s and 1990s is marketing a new series of posters. They do a new mailing to 5,000 of their customers to evaluate who is most likely to buy the new poster series. It costs $0.25 to mail the promotion to each customer and the expected contribution from each customer is approximately $10 (revenue from each customer is approximately $15). They then ran a decision tree analyses (the output is listed below):

1. How many terminal nodes are there?

1. What is the best predictor of buying overall?

1. Describe one interaction in the analysis.