The existence policy is an easy way to define how often an object exists and under what conditions. For certain existence policies, you can add tags to define existence properties by clicking on the Settings option in the toolbar, then on the Context Generator.
Always Exist: Default setting for all objects. The object will exist at each instance of parcel expansion.
Float Greater Than Tag: Object exists when object tag value is equal to or greater than an assigned value. The assigned value here consists of a decimal value (for example, 4.5 or 2.8).
Int Greater Than Tag Value: Object exists when object tag value, here defined as an integer, is greater than an assigned value.
Int Tag Value: Object exists when object tag value, here defined as an integer, is equal to an assigned value.
Maybe Exist Policy: Object exists X percent of the time. X is an integer ranging from 1 to 100, as you see in the drop-down box.
String Tag Value: Object exists as function of a defined tag.