Private and continual release of statistics

We ask the question: how can Web sites and data aggregators continually release updated statistics, and meanwhile preserve each individual users privacy? Suppose we are given a stream of 0s and 1s. We propose a differentially private continual counter that outputs at every time step the approximate number of 1s seen thus far. Our counter construction has error that is only poly-log in the number of time steps. We can extend the basic counter construction to allow Web sites to continually give top-k and hot items suggestions while preserving users privacy.

Citation

Chan, H.; Shi, E.; Song, D. Private and continual release of statistics. ACM Transactions on Information and System Security. 2011 November; 14 (3): article 26.