Each match purpose supports a combination of mandatory and optional fields. Each field is weighted according to its influence in the match decision. Some fields in some purposes may be grouped. There are two types of groupings:

Required—requires at least one of the field members to be non-null
Best of—contributes only the best score from the fields in the group to the overall match score

For example, in the Individual match purpose:

Person_Name is a mandatory field
One of either ID Number or Date of Birth is required
Other attributes are optional

The overall score returned by each purpose is calculated by adding the participating field scores multiplied by their respective weight and divided by the total of all field weights. If a field is optional and is not provided, it is not included in the weight calculation.