According to the Yerkes-Dodson law, people tend to perform best when they have some anxiety about a task. However, not enough anxiety and too much anxiety have been shown to dampen performance. Figure 14.30 shows five scatterplots of the relationships between these variables.

a. Which variable is on the x axis? Which is on the y axis? How do you know?

b. Which scatterplot depicts the Yerkes-Dodson law? Explain how you know.

c. Is it appropriate to calculate the correlation coefficient for the relationship between anxiety and performance, as given by the Yerkes-Dodson law?
Explain your answer.