=+17. Movie budgets. How does the cost of a movie depend on its length? Data on the cost (millions of dollars) and the running time (minutes) for major release films in one recent year are summarized in these plots and computer output:

200 150 100 0

50 80 100 120 140 160 180 200 Budget ($M)

Run Time (minutes)

Dependent variable is: Budget($M)

R-squared = 15.4%

s = 32.95 with 120 - 2 = 118 degrees of freedom Variable Coefficient SE(Coeff) t-Ratio P-Value Intercept -31.39 17.12 -1.83 0.0693 Run time 0.71 0.15 4.64 60.0001 100 50 0

–50 20 40 60 80 100 120 140 Residuals Predicted 100 50 0

–50

–2 –1 0 1 2 3 Residuals Normal Scores