11. A system comprising: a machine including a memory and at least one processor; a interaction module configured to: access interaction data describing one or more interactions between at least one actor of a plurality of actors of an online social network service and one or more content items accessible on the online social network service; and identify, based on the interaction data, a specific content item posted by a particular actor of the plurality of actors and one or more interactions by respective other actors of the plurality of actors with the specific content item; and a leadership module, executable by the machine, configured to: calculate, based on the interaction data, a leadership score associated with the particular actor, the leadership score indicating a propensity of the particular actor to spread information among the plurality of actors of the online social network service; determine a number of actors from the plurality of actors have each disseminated the specific content item within a predetermined time period after the specific content item was uploaded to the online social network service by the particular actor, the number of actors being within a predetermined number range; and classify, based at least in part on the calculated leadership score, the particular actor as an information propagator among the plurality of actors of the online social network service.
11. A system comprising: a machine including a memory and at least one processor; a interaction module configured to: access interaction data describing one or more interactions between at least one actor of a plurality of actors of an online social network service and one or more content items accessible on the online social network service; and identify, based on the interaction data, a specific content item posted by a particular actor of the plurality of actors and one or more interactions by respective other actors of the plurality of actors with the specific content item; and a leadership module, executable by the machine, configured to: calculate, based on the interaction data, a leadership score associated with the particular actor, the leadership score indicating a propensity of the particular actor to spread information among the plurality of actors of the online social network service; determine a number of actors from the plurality of actors have each disseminated the specific content item within a predetermined time period after the specific content item was uploaded to the online social network service by the particular actor, the number of actors being within a predetermined number range; and classify, based at least in part on the calculated leadership score, the particular actor as an information propagator among the plurality of actors of the online social network service. 12. The system of claim 11 , wherein the leadership module is further configured to: calculate the leadership score based in part on one of: a number of social network followers of the particular actor or a number of social network connections of the particular actor on the online social network service.