Anonymity revisited: the degree of the knowledge transfer

Anonymity has been regarded mainly as anonymity of the person who did something. We believe that the anonymity of the subject may not be a primary concern and the more important part would be the fact that the subject did some deed. We focus on the relationship of the subject and the deed. Another argument we raise here is the need of quantitative measures for the anonymity. Anonymity has been dealt only as a quality, but we need to quantise the quality to measure and compare anonymising mechanisms. We provide a metric, we call it anonymity metric, in order to measure the anonymity of mechanisms. As a typical example for anonymising mechanisms, we consider electronic voting schemes. Secret ballot definitely needs not to expose relationship between voter and his ballot. On this basis, most electronic voting schemes have been designed to keep anonymity of voters and nontraceability of ballots. We apply the anonymity metric to anonymous mechanisms in voting schemes and present metric computations.