Chapter 27, Problem 19E

a)

To determine

To find the 95% confidence interval for the slope of the regression line.

Answer to Problem 19E

  $(-9.5612,-6.8660)$

Explanation of Solution

Given:

  

Formula:

Confidence interval for slope is,

  $(Coefficient(b)\mp 2\times S{E}_b)$

Using formula, 95% confidence interval for the slope of the regression line.

  $\begin{array}{l}(-8.21362-2\times 0.6738,-8.21362-2\times 0.6738)\\ (-9.5612,-6.8660)\end{array}$

b)

To determine

To explain the 95% confidence interval for the slope of the regression line.

Answer to Problem 19E

We are 95% confident that the slope of the population regression line is between -9.5707 and -6.8566.

Explanation of Solution

Given:

  

95% confidence interval for the slope of the regression line:

  $(-9.5612,-6.8660)$

We are 95% confident that the slope of the population regression line is between -9.5707 and -6.8566.