Does Training in a Memory Program Affect Memory for Spontaneously

Does training in a memory program affect memory for spontaneously observed events? A researcher arranged to train four volunteers in a memory program and four other volunteers served as controls. A week later, as part of their psychology class, all eight volunteers watched a film showing a bank robbery. Afterward they were questioned about the events. The number of accurate responses for the participants who had taken the memory course were 20, 25, 24, and 23. The number of correct responses for the control-group participants were 14, 22, 18, and 17. Do these results support the contention that those trained in this particular memory program are more accurate at recall for spontaneously observed events? (Use the .05 significance level.)
a. Use the five steps of hypothesis testing.
b. Figure the effect size.
c. Explain what you did to a person who is familiar with the t test for a single sample but is unfamiliar with the t test for independent means.