Oil and residuals Exercise 59 on page 193 (Chapter 3) examined data on the depth of small defects in the Trans-Alaska Oil Pipeline. Researchers compared the results of measurements on 100 defects made in the field with measurements of the same defects made in the laboratory. The figure below shows a residual plot for the least-squares regression line based on these data. Are the conditions for performing inference about the slopeβ of the population regression line met? Justify your answer.

Short Answer

Expert verified

The equal variance requirement has not been met.

Step by step solution

01

Given Information

Need to find which variance requirements have not been met.

02

Explanation

There are five conditions for regression inference are: Linear, Independent, Normal, Equal variance, Random

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.

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