Title: Building and Measuring Privacy-Preserving Mobility Analytics - view slides
Abstract: Location data can be extremely useful to study commuting patterns and disruptions, as well as to predict real-time traffic volumes. At the same time, however, the fine-grained collection of user locations raises serious privacy concerns, as this can reveal sensitive information about the users, such as, life style, political and religious inclinations, or even identities. In our paper, we study the feasibility of crowd-sourced mobility analytics over aggregate location information: users periodically report their location, using a provably secure, privacy-preserving aggregation protocol, so that the server can only recover aggregates — i.e., how many, but not which, users are in a region at a given time. We experiment with real-world mobility datasets obtained from the Transport For London authority and the San Francisco Cabs network, and present a novel methodology based on time series modeling that is geared to forecast traffic volumes in regions of interest and to detect mobility anomalies in them. In the presence of anomalies, we also make enhanced traffic volume predictions by feeding our model with additional information from correlated regions. Finally, we discuss challenges related to the possible privacy leakage from the aggregates themselves, as well as other applications of privacy-friendly analytics from aggregate statistics.
Bio: Emiliano De Cristofaro is a Senior Lecturer (~Associate Professor) in the Computer Science Department of the University College London (UCL). Prior to joining UCL, he was a Research Scientist at PARC, a Xerox Company. He received a PhD in Networked Systems from the University of California Irvine, advised by Prof. Gene Tsudik. His research interests include privacy technologies, applied cryptography, and web security/privacy measurements. In 2012, he received an Excellency Award from PARC’s Computer Science Lab. He co-chaired the Privacy Enhancing Technologies Symposium (PETS) in 2013-2014, and the Workshop on Genome Privacy and Security (GenoPri) in 2015. More info at https://emilianodc.com.