*Robust Regression Examples* |

## Example 9.7: Stackloss Data

The following two graphs show

- the plot of standardized LMS residuals vs. robust distances
*RD*_{i}
- the plot of standardized LS residuals
vs. Mahalanobis distances
*MD*_{i}

In the first plot, you see that case 4 is a regression
outlier but not a leverage point, so it is a vertical outlier.
Cases 1, 3, and 21 are bad leverage points,
whereas case 2 is a good leverage point.
Note that case 21 lies near the boundary line between vertical
outliers and bad leverage points and that case 2 is very
close to the boundary between good and bad leverage points.
The output follows.

**Output 9.7.1:** Stackloss Data: LMS Residuals vs. Robust Distances

**Output 9.7.2:** Stackloss Data: LS Residuals vs. Mahalanobis Distances

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