When paths cross: maintaining utility of trajectory data in geomasking

Abstract

With an increase in mobile data collection through GPS and other location-based services, there have been a number of attempts to apply geomasking techniques to published route data in order to protect trajectory privacy. Yet, the utility of masked trajectory data and its value to transportation research remain in question. This study examines how the inferred route changes when origin and destination data are masked to protect privacy, as well as calculates the anonymity of each route traveled by a sample of New York City taxi cabs. It is determined that the routes between locations masked by random perturbation are significantly different from the original routes and that a network-based data product suppressing unique routes is a viable solution to release both accurate route statistics and protect confidentiality