Chapter 4, Problem 74SE

Test Scores Assume that in a sociology class, the teacher gives a midterm exam and a final exam. Assume that the association between midterm and final scores is linear. Here are the summary statistics:

Midterm: Mean $=72$, Standard deviation $=8$

Final: Mean $=72$, Standard deviation $=8$

Also, $r=0.75$ and $n=28$.

a. Find and report the equation of the regression line to predict the final exam score from the midterm score.

b. For a student who gets 55 on the midterm, predict the final exam score.

c. Your answer to part (b) should be higher than 55. Why?

d. Consider a student who gets a 100 on the midterm. Without doing any calculations, state whether the predicted score on the final exam would be higher, lower, or the same as 100.