How To Remove Outliers

Numbers that do not fit with the rest of your results could create false conclusions.

Outliers are numerical results that do not fit in with the other numbers in the resulting series. This is something that is often produced in the engineering program Simulink Design Optimization. For example, if your results produce a series of numbers between 20 and 30 but that same result also includes the numbers 3 and 89, the latter two numbers are the outliers. These numbers can reduce the accuracy of your results. Therefore, you will want to remove these results in most cases.

Instructions

1. Click the "Output Data" tab located in the "DataSet1" section of the "Control and Estimation Tools" manager. Select the cell labeled "position1(:,1)*" in this area. This will open the results for viewing so that you can see the outliers.

2. Click "Pre-Process" on the "Output Data" window to update the Graphical User Interface (GUI) in relation to the "position1(:,1)*" cell.

3. Click the "Exclusions Rule" tab and then the box labeled "Outliers." A check mark will appear in the box to show that it is now selected for showing outliers.

4. Select "DataSet1" from the "Existing Dataset" drop-down menu located within the "Write Results" section of the work space. This option should remain selected but may not already be automatically selected.

5. Click the button entitled "Add." This will make a box appear that is titled the "Update Table Data." The box will ask whether you would like to override or update the information in the "position1(:,1)*" cell. Click "Yes" to update this cell. This will remove outliers making them disappear from all results and graphs. They will be replaced with "NaNs" in the results.

References

• Math is Fun: Outlier
• Mathworks: Removing Outliers