One of the most famous national highways from its beginnings in the 1920s until its demise around 1970 was Route 66. On its way from Chicago to Los Angeles, one of the last stops was San Bernardino, California. Now, a new transportation hub-the San Bernardino International Airport-is in the planning stages. Although no agreements with any air carriers have been signed, officials forecast 2 million passengers by 2030, as shown in the following table.4

Linear and quadratic fitted plots for these data follow.

Question continue over next page

a. Based on the summary statistics in the line plots, which of the two models better fits the data?
b. Write the theoretical equation for the quadratic model.
c. Use the following printout to determine if the quadratic model contributes significant information to the prediction of y.
d. Use the following printout to determine if the quadratic term contributes significant information to the prediction of y, in the presence of the linear term.
Regression Analysis: y versus x, x-sq
The regression equation is
y = 400000 + 53571 x + 53571 x-sq

Transcribed Image Text:

Year Coded Year, x 1 Number of Travelers, y 500,000 750,000 1,000,000 1,500,000 2,000,000 2010 2015 2020 2025 2030 Fitted Line Plot у 25000 + 375000 х 20D000) 1750000 1500000 1250000 1O000OD R-Sq R-Sq(adj) 120761 97.0% 96.0% 750000 500000 Fitted Line Plot y 400000 53571 x 53571 x**2 2000000 1750000 R-Sq R-Sq(adj) 42257.7 99.8% 99.5% 1500000 1250000- 1000000 750000 500000 4 Predictor Constant 400000 2 x-sq Coef SE Coef 53571 53571 90633 4.41 0.048 69068 0.78 0.519 11294 4.74 0.042 S 42257.7 R-Sq 99.8% R-Sg(adj ) 99.5% - # Analysis of Variance Source Regression Residual Error 2 3571428571 1785714286 Total DF MS 2 1.44643E+12 7.23214E+11 405.00 0.002 4 1.45000E+12