Grades? The professor teaching the Introductory Statistics class discussed in Exercise 39 wonders whether performance on homework can accurately predict midterm scores.

a) To investigate it, she fits a regression of the sum of the two midterms scores on homework scores. Fit the regression model.

b) Comment on the model including a discussion of the assumptions and conditions for regression. Is the coefficient for the slope statistically significant ?

c) Do you think she can accurately judge a student s performance without giving the midterms? Explain.