Determining accuracies with which types of user identifying information identify online system users

A computer program product comprising a computer readable storage system having instructions encoded thereon that, when executed by a processor, cause the processor to:

• receive, at an online system, user identifying information describing one or more users of a third party system;
• compare the received information to user identifying information maintained by the online system and describing one or more users of the online system;
• for each comparison of user identifying information describing a user of a third party system to user identifying information describing a user of the online system:
• determine a score associated with the user of the online system based at least in part on one or more types of user identifying information describing the user of the online system matching one or more types of user identifying information describing the user of the third party system;
• for one or more sets including one or more types user identifying information, determine a measure of accuracy of a set based at least in part on one or more scores associated with users of the online system having the one or more types of user identifying information in the set describing the one or more users of the online system matching the one or more types of user identifying information in the set describing at least one user of the third party system;
• and
• generate a ranking of the one or more sets of user identifying information based at least in part on the determined measures of accuracy.

A method comprising:

• receiving, at an online system, an indication of one or more types of user identifying information describing a user of a third party system matching one or more types of user identifying information describing a user of the additional third party system;
• retrieving data maintained by the online system including measures of accuracy associated with a plurality of sets of types of user identifying information, a measure of accuracy associated with a set of user identifying information based at least in part on users of the third party system online having one or more types of user identifying information in the set matching the one or more types of user identifying information in the set associated with at least one user of the additional third party system;
• identifying a selected set of types of user identifying information including the one or more types of user identifying information included in the received indication and associated with a maximum measure of accuracy;
• and
• communicating the identified maximum measure of accuracy to the third party system.