About Selecting Type Fields
By default, "None" is selected as the type field. When "None"
is selected all features are used in the classification and share
the same the
spatial relationship,
buffer distance, and destination class. However, there are situations
where you may want to exclude features from the classification or
treat them differently in terms of a spatial relationship, buffer
distance, and/or the destination class.
Learn
more about toggling the use of types
Example of Using a Type Field
Different buffer distances and destination classes are used for
different type values