4. Advanced Composition Theorems8:
Advanced composition theorems are mathematical tools that provide more
accurate and tighter privacy bounds when combining multiple queries or
computations in differential privacy. They are designed to address some
of the limitations of basic composition techniques and offer more
precise quantification of cumulative privacy loss. Two prominent
examples of advanced composition theorems are the Moments Accountant and
Rényi Differential Privacy.
1. Moments Accountant: The Moments Accountant is a technique used to
analyze the privacy loss that accumulates over a sequence of queries. It
takes into account the higher moments of the privacy loss distribution,
allowing for tighter and more accurate privacy bounds compared to
traditional methods. By considering a broader view of the privacy loss
distribution, the Moments Accountant provides a more refined estimation
of the cumulative privacy guarantee.
2. Rényi Differential Privacy: Rényi Differential Privacy is an
extension of the traditional ε-differential privacy concept. It
introduces a parameter α that allows for varying levels of privacy
protection. When α approaches infinity, Rényi Differential Privacy
converges to pure ε-differential privacy. For smaller values of α, Rényi
privacy provides tighter privacy bounds compared to basic composition
techniques, particularly in settings with a large number of queries.