RON-Gauss: Enhancing Utility in Non-Interactive Private Data Release
This work addresses the problem of privacy-preserving data release for real-world machine learning applications, offering a novel method that enhances utility while ensuring strong privacy guarantees.
The paper tackles the challenge of maintaining data utility in non-interactive differential privacy by proposing the RON-Gauss model, which combines random orthonormal projection and Gaussian generative models to synthesize private data, resulting in up to an order of magnitude improvement over previous approaches with minimal utility loss.
A key challenge facing the design of differential privacy in the non-interactive setting is to maintain the utility of the released data. To overcome this challenge, we utilize the Diaconis-Freedman-Meckes (DFM) effect, which states that most projections of high-dimensional data are nearly Gaussian. Hence, we propose the RON-Gauss model that leverages the novel combination of dimensionality reduction via random orthonormal (RON) projection and the Gaussian generative model for synthesizing differentially-private data. We analyze how RON-Gauss benefits from the DFM effect, and present multiple algorithms for a range of machine learning applications, including both unsupervised and supervised learning. Furthermore, we rigorously prove that (a) our algorithms satisfy the strong $ε$-differential privacy guarantee, and (b) RON projection can lower the level of perturbation required for differential privacy. Finally, we illustrate the effectiveness of RON-Gauss under three common machine learning applications -- clustering, classification, and regression -- on three large real-world datasets. Our empirical results show that (a) RON-Gauss outperforms previous approaches by up to an order of magnitude, and (b) loss in utility compared to the non-private real data is small. Thus, RON-Gauss can serve as a key enabler for real-world deployment of privacy-preserving data release.