1. A method for associating an entity of a contact with a character string, wherein a database stores a plurality of contacts, and each contact has a defined set of entities, comprising: evaluating, for a first subgroup of the defined set of entities, using a processor, a structure of the character string, wherein if the structure is recognized, the character string is associated with at least one of the entities in the first subgroup; and, if the structure is not recognized, evaluating, for a second subgroup of the defined set of entities, using a processor, a probabilistic approximation that the character string is associated with at least one of the entities in the second subgroup.