The LSV seminar takes place on Tuesday at 11:00 AM. The usual location is the conference room at Pavillon des Jardins (venue). If you wish to be informed by e-mail about upcoming seminars, please contact Stéphane Le Roux and Matthias Fuegger.
The seminar is open to public and does not require any form of registration.
With the increasing popularity of GPS-enabled handheld devices, location based services (LBS) have access to accurate location information, raising serious privacy concerns for end users. Trying to address these issues, the notion of geo-indistinguishability was recently introduced, protecting privacy by reporting to the LBS only a noisy version of the user's location.
Standard geo-indistinguishability works well in the case of a sporadic use, however, under repeated use over time, constantly applying noise leads to a quick loss of privacy.
In the first part of this thesis we show that correlation in the trace can be in fact exploited through a prediction function that tries to guess the new location reducing the number of sanitized positions.
Another drawback of geo-indistinguishability is that it treats space in a uniform way, imposing the addition of the same amount of noise everywhere on the map. In the second part of this thesis we propose a novel elastic mechanism that adapts the level of noise to the different degrees of density of each area.