16.31 Online bookstore prices.
For more than 80 years, the New York Times has been publishing its weekly list of best-selling books in the United States. For certain book subcategories, the best-selling lists are done monthly. On the New York Times best-selling book website, there is a “buy” button next to each listed book. The button directs the viewer to one of two online bookstore options: Amazon or Barnes & Noble. Consider the following table of the online prices of the best-selling business books for September 2014. Note that older titles are paperback versus paperback comparisons, while newer titles are hardback versus hardback comparisons.11
nytbook
16-22
| Book title | Barnes & Noble price ($) | Amazon price ($) |
| Outliers | 10.39 | 10.19 |
| The Path Between the Seas | 13.44 | 13.18 |
| Thinking, Fast and Slow | 9.99 | 9.90 |
| The Power of Habit | 9.97 | 9.78 |
| #GIRLBOSS | 16.25 | 16.17 |
| The Organized Mind | 18.03 | 17.68 |
| Capital in the Twenty-First Century | 24.08 | 23.97 |
| Think Like a Freak | 17.73 | 17.73 |
| Business Adventures | 10.25 | 10.25 |
| Lean In | 16.11 | 16.03 |
Is there is a systematic difference in book prices between the two online booksellers? Formulate this question in terms of null and alternative hypotheses. Then compute the differences and find the value of the Wilcoxon signed rank statistic .
16.31
H0: There is no difference in the distribution of price between Barnes & Noble and Amazon. Ha: One online retailer has systematically higher prices than the other. .