The more vertical the lines are, the less accurate the line fitting becomes. The problem seems to be that the residuals are only calculated based on the difference in the y-values
When the line is visualized, you can see that it is often diagonal and not centered:
The more vertical the lines are, the less accurate the line fitting becomes. The problem seems to be that the residuals are only calculated based on the difference in the y-values
When the line is visualized, you can see that it is often diagonal and not centered: