1. A method comprising: receiving a plurality of user account identifiers by a computing device; receiving a plurality of messages, wherein each message is associated with a user account and a time by the computing device; receiving a question by the computing device, wherein the question is associated with a time; determining a subset of the plurality of user account identifiers based on the messages associated with the user accounts, the times associated with the messages, the question, and the time associated with the question by the computing device; and providing the determined subset by the computing device.
1. A method comprising: receiving a plurality of user account identifiers by a computing device; receiving a plurality of messages, wherein each message is associated with a user account and a time by the computing device; receiving a question by the computing device, wherein the question is associated with a time; determining a subset of the plurality of user account identifiers based on the messages associated with the user accounts, the times associated with the messages, the question, and the time associated with the question by the computing device; and providing the determined subset by the computing device. 8. The method of claim 1 , wherein the user account identifiers are identifiers of user accounts in one or more social networking applications.