Chapter 12.1, Problem 1E

To determine

To explain are the conditions for performing inference about the slope $\beta$ of the population regression line met.

Answer to Problem 1E

They have not been made.

Explanation of Solution

In the question researchers examined data on the depth of small defects in Trans-Alaska Oil Pipeline. And they compared the results of measurements made in the field with measurements of the same defects made in the laboratory. And the residual plot is given for the least square line based on these data. Thus, as we know there are five conditions for regression inference are: Linear, Independent, Normal, Equal variance, Random. Therefore, the Equal variance requirement has not been met, because the vertical spread is larger to the right than it is to the left in the residual plot.