Using the Training Sites Editing window

In the Training Sites Editing window, you can use either the active training layer or, if necessary, select a layer to use for training. You then select the field you want to use, which stores the class information for both training and accuracy-assesment samples. With each class you add, you can edit the class name and assign a color to it. After you add a class, you then select the polygons you want to assign to the class, and then assign them accordingly. You then designate whether the class is for training or accuracy assessment. Finally, you set up the training sites to identify potential outliers.

To use the Training Sites Editing window

In the Training layer box, type or select the layer you want.
If the layer you want is not in the list, click Load, and then in the Select Vector Layer window, in the File box, type or select the path and file name of the file you want. If the file is not in the list, click Browse, and then select the file you want.
In the Training Sites Editing window, in the Training field box, type or select the field you want or, to create a field, click Create.
If you are creating a field, in the Training Field window, type the name you want in the Field name box, and then click OK. The field is added to the list of available fields in the Training field box (and to the attribute table, which you can view in Attribute Manager).

Note: The name of the class (the value of the training field) will be appended with a prefix based on whether Sample type is Training or Accuracy assessment.
After you select the layer and field you want, click Add Class.
The class is added to the table. If necessary, you can edit the class name and assign a color to a class.
Do the following:
- If you want to assign a color to a class, select it, and then in the Color column, click to open the color palette, and then select the color you want.
- In the table, select a class to which you want to assign one or more polygons, and then click Individual Select.
- In the viewer, click one or more polygons, and then in the Training Sites Editing window, click Assign.
  The polygon or polygons you selected are added to the class, as shown in the Training Count column or Accuracy Count column, as applicable.
- Repeat until you have added as many classes as you need and assigned as many polygons as you require to each class.
Beside Sample type, do one of the following:
- To use the selected class for training, make sure Training is selected.
  When you view the class name in Attribute Manager, it is prefixed with _T.
- To use the selected class for accuracy assessment, click Accuracy Assessment.
  When you view the class name in Attribute Manager, it is prefixed with _A.
To identify potential outliers in the selected set of each class, expand Class Outliers, and then do the following:
- In the Fields list, select the check box beside one or more of the fields on which you want to perform the analysis.
- In the Algorithm list, select the algorithm to use: Interquartile range, 3 sigma (away from mean), or 2 sigma (away from mean).
- Click Select Outliers.
  If any outliers are found, each appears as selected in the viewer.
After you have added all the classes you want, click Close to return to setting up Training Sites Editing.