14. A candidate selection system for finding matches between entities, comprising: at least one machine learning system which includes: at least one non-transitory processor-readable medium that stores processor-executable instructions; and at least one processor communicably coupled to the at least one non-transitory processor-readable medium and which executes the processor-executable instructions to: implement the at least one machine learning system including an input layer, an output layer and a hidden layer, the at least one machine learning system trained with at least a first entity and a second entity that are a historically successful pairing, and trained with a plurality of hypothetical alternative pairings between the first entity of the historically successful pairing and other entities of a first set of entities, the hypothetical alternative pairings based on at least one value of at least one attribute of a plurality of attributes associated with the second entity and at least one loosened constraint of a number of constraints on matching the at least one value of the at least one attribute associated with the second entity; and at least one processor-based system, the at least one processor-based system communicatively coupled to the machine learning system, the at least one processor-based system includes: at least one non-transitory processor-readable medium that stores processor-executable instructions; and at least one processor communicably coupled to the at least one non-transitory processor-readable medium and which executes the processor-executable instructions to: receive a number of heuristic values indicative of a strength of a pairing between the first entity and at least one of the entities of the first set of entities; and execute a candidate selection algorithm which employs the received heuristic values and respective values for each of the plurality of attributes to identify prospective candidates within a second set of entities.
14. A candidate selection system for finding matches between entities, comprising: at least one machine learning system which includes: at least one non-transitory processor-readable medium that stores processor-executable instructions; and at least one processor communicably coupled to the at least one non-transitory processor-readable medium and which executes the processor-executable instructions to: implement the at least one machine learning system including an input layer, an output layer and a hidden layer, the at least one machine learning system trained with at least a first entity and a second entity that are a historically successful pairing, and trained with a plurality of hypothetical alternative pairings between the first entity of the historically successful pairing and other entities of a first set of entities, the hypothetical alternative pairings based on at least one value of at least one attribute of a plurality of attributes associated with the second entity and at least one loosened constraint of a number of constraints on matching the at least one value of the at least one attribute associated with the second entity; and at least one processor-based system, the at least one processor-based system communicatively coupled to the machine learning system, the at least one processor-based system includes: at least one non-transitory processor-readable medium that stores processor-executable instructions; and at least one processor communicably coupled to the at least one non-transitory processor-readable medium and which executes the processor-executable instructions to: receive a number of heuristic values indicative of a strength of a pairing between the first entity and at least one of the entities of the first set of entities; and execute a candidate selection algorithm which employs the received heuristic values and respective values for each of the plurality of attributes to identify prospective candidates within a second set of entities. 22. The candidate selection system of claim 14 wherein a plurality of messages sent to the first entity by other ones of the entities are presented to the first entity in a ranked order, the ranked order reflecting a strength of a pairing between the first entity and the other ones of the entities.