Question: How does sleep affect memory? To find out, eight students learned a list of 10 nonsense words. For the next 4 hours, half of them slept and half engaged in daytime activities. Then each was tested on the list. The next day everyone learned a new list. Those who had slept did daytime activities and those who were awake the day before slept for 4 hours. Each recalled the new list. The table shows the number of words each person recalled under the two conditions. Establish a 95 percent confidence interval about the difference between the two means, and write an interpretation that includes a statement about the fate of the null hypothesis when a =.05. (Based on a 1924 study by Jenkins and Dallenbach.)

Asleep             Awake

4                       2

3                       2

5                       4

3                       0

2                       4

4                       3

3                       1

6                       4