Chapter 16.1, Problem 5E

In working further with the problem of exercise 4, statisticians suggested the use of the following curvilinear estimated regression equation.

$\hat{y}=b_0+b_{1}x+b_2{x}^2$

1. a. Use the data of exercise 4 to compute the coefficients of this estimated regression equation.
2. b. Using α = .01, test for a significant relationship.
3. c. Estimate the traffic flow in vehicles per hour at a speed of 38 miles per hour.

4. A highway department is studying the relationship between traffic flow and speed. The following model has been hypothesized.

$y={\beta }_0+{\beta }_{1}x+\in$

where

y = traffic flow in vehicles per hour

x = vehicle speed in miles per hour

The following data were collected during rush hour for six highways leading out of the city.

1. a. Develop an estimated regression equation for the data.
2. b. Using α = .01, test for a significant relationship.