Chapter 4, Problem 35E

Caffeine A student study of the effects of caffeine asked volunteers to take a memory test 2 hours after drinking soda. Some drank caffeine-free cola, some drank regular cola (with caffeine), and others drank a mixture of the two (getting a halfdose of caffeine). Here are the 5-number summaries for each group’s scores (number of items recalled correctly) on the memory test:

1. a) Describe the W’s for these data.
2. b) Name the variables and classify each as categorical or quantitative.
3. c) Create side-by-side boxplots to display these results as best you can with this information.
4. d) Write a few sentences comparing the performances of the three groups.