%0 Journal Article %J Journal of Trust Management %D 2015 %T A risk model for privacy in trajectory data %A Anirban Basu %A Anna Monreale %A Roberto Trasarti %A Juan Camilo Corena %A Fosca Giannotti %A Dino Pedreschi %A Shinsaku Kiyomoto %A Yutaka Miyake %A Tadashi Yanagihara %X Time sequence data relating to users, such as medical histories and mobility data, are good candidates for data mining, but often contain highly sensitive information. Different methods in privacy-preserving data publishing are utilised to release such private data so that individual records in the released data cannot be re-linked to specific users with a high degree of certainty. These methods provide theoretical worst-case privacy risks as measures of the privacy protection that they offer. However, often with many real-world data the worst-case scenario is too pessimistic and does not provide a realistic view of the privacy risks: the real probability of re-identification is often much lower than the theoretical worst-case risk. In this paper, we propose a novel empirical risk model for privacy which, in relation to the cost of privacy attacks, demonstrates better the practical risks associated with a privacy preserving data release. We show detailed evaluation of the proposed risk model by using k-anonymised real-world mobility data and then, we show how the empirical evaluation of the privacy risk has a different trend in synthetic data describing random movements. %B Journal of Trust Management %V 2 %P 9 %G eng %R 10.1186/s40493-015-0020-6