Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

{Exercise 16.5} http://cnow.apps.ng.cengage.com/ilrn/books/asmb05h/images/ch16/a

ID: 3172211 • Letter: #

Question

{Exercise 16.5} http://cnow.apps.ng.cengage.com/ilrn/books/asmb05h/images/ch16/asmb05h_ch16_ex4.gif File: data16-05.xls Using the data above, statisticians suggested the use of the following curvilinear estimated regression equation. a. Use the data to compute the b1 coefficient of this estimated regression equation (to 4 decimals). b1 = (Create the xSquare variable first using Data/Transform Data/Square.) b. Using = .01, test for a significant relationship. F = (to 2 decimals) p-value = The relationship significant. c. Estimate the traffic flow in vehicles per hour at a speed of 38 miles per hour (to 2 decimals). 95% Prediction interval = (n1,n2)

Explanation / Answer

The regression equation is
Traffic = 943 + 8.71 Speed


Predictor Coef SE Coef T P
Constant 943.05 59.38 15.88 0.000
Speed 8.714 1.544 5.64 0.005


S = 32.2940 R-Sq = 88.8% R-Sq(adj) = 86.1%


Analysis of Variance

Source DF SS MS F P
Regression 1 33223 33223 31.86 0.005
Residual Error 4 4172 1043
Total 5 37395

a) The coefficient of b1 is 8.71 .

b) Ans: The estimaed p-value of b1 is 0.005 and less than 0.01. Hence, the slope of vehivle speed has significant effect on traffic folw.

c) The traffic flow in vehicles per hour at a speed of 38 miles per hour (to 2 decimals) is

Traffic = 943 + 8.71*38=1273.98.

95% Prediction interval = (n1,n2)= ({943 + 8.71*(38-1.96*1.544)}, {943 + 8.71*(38+1.96*1.544)})

= (1247.621, 1300.339)