Research

WATA
In public competition or university exams, procedures for the anonymous marking of examination scripts are a open problem. Some solution like the double envelope method, require that candidates trust on the examiner's fairness. Other solutions require an effort for candidates in the examination venue, affecting the usability of the system. WATA (Bella et al.,2010) faces the contradictory combination of candidate authentication together with anonymous marking, since its first release. Nevertheless, new secure properties are required such as auditability and verifiability, and the system should be managed remotely. The focus of the current work is to advance a novel version of WATA that achieves all of the desired requirements.

Differential Privacy
The right of privacy means that individuals get to decide what and how much information to release, whom it is given, and for what uses. Often, privacy is confused with anonymity, which allows individual's personal identity to be publicly unknown. This mess has led to many privacy leak issues. Differential privacy aims to minimize the risk incurred by an individual who joins a database. The contribution on this field is the definition of what seems to be the first differential-privacy preserving function with non-numeric values. In particular,  the function is built using the exponential mechanism, which is a generic and data-type independent method to obtain differential privacy, and could be used to enforce privacy in e-commerce.