1. A computer-implemented method for correcting location data, comprising: receiving a reported location of a mobile device; determining a set of possible geographic locations for the mobile device based at least in part on the reported location and a device density map describing a historical distribution of mobile devices over a geographic region; determining a probability for each location in the set of possible geographic locations, each probability indicating a likelihood that an associated possible geographic location represents a true location of the mobile device, wherein determining the probability comprises: determining a traversed path of the mobile device based on previously determined locations of the mobile device through one or more cell regions, of a plurality of cell regions, that together cover the geographic region, determining one or more historical paths that traverse one or more of the cell regions, and have at least one cell region in common with the traversed path, and determining a probability that a location in the set of possible geographic locations is the true location based on comparisons between the one or more historical paths and the traversed path; selecting a possible geographic location in the set responsive to the determined probabilities; and publishing the true location of the mobile device based at least in part on the selected possible geographic location.