1. A computer-implemented method comprising: receiving microposts comprising tokens; identifying a subset of the microposts that comprise a given token; determining a subset geographic location corresponding to the subset of the microposts that comprise the given token, wherein determining the subset geographic location comprises identifying microposts associated with geo-tags, identifying micropost geographic locations associated with respective ones of the identified microposts based at least in part on the geo-tags, and applying a clustering algorithm to the micropost geographic locations to identify the subset geographic location, at least in part by determining that the micropost geographic locations have a cluster density about the subset geographic location; associating the given token with the subset geographic location; and updating an index to reflect an association between the given token and the subset geographic location.