The CASE histogram: privacy-aware processing of trajectory data using aggregates

Abstract

Due to the high uptake of location-based services (LBSs), large spatio-temporal datasets of moving objects’ trajectories are being created every day. An important task in spatial data analytics is to service range queries by returning trajectory counts within a queried region. The question of how to keep an individual user’s data private whilst enabling spatial data analytics by third parties has become an urgent research direction. Indeed, it is increasingly becoming a concern for users. To preserve privacy we discard individual trajectories and aggregate counts over a spatial and temporal partition. However the privacy gained comes at a cost to utility: trajectories passing through multipl..