Differentially-Private Data Synthetisation for Efficient Re-Identification Risk Control

TL;DR

This paper introduces $\ extepsilon$-PrivateSMOTE, a new differentially private synthetic data generation method that effectively reduces re-identification risk while maintaining high data utility and computational efficiency.

Contribution

The paper presents $\ extepsilon$-PrivateSMOTE, a novel synthetic data generation technique combining noise-induced interpolation with differential privacy, offering a resource-efficient alternative to existing methods.

Findings

Achieves competitive privacy risk reduction compared to state-of-the-art methods.

Improves computational efficiency by at least a factor of 9.

Maintains high predictive performance with lower resource requirements.

Abstract

Protecting user data privacy can be achieved via many methods, from statistical transformations to generative models. However, all of them have critical drawbacks. For example, creating a transformed data set using traditional techniques is highly time-consuming. Also, recent deep learning-based solutions require significant computational resources in addition to long training phases, and differentially private-based solutions may undermine data utility. In this paper, we propose $\epsilon$-PrivateSMOTE, a technique designed for safeguarding against re-identification and linkage attacks, particularly addressing cases with a high \sloppy re-identification risk. Our proposal combines synthetic data generation via noise-induced interpolation with differential privacy principles to obfuscate high-risk cases. We demonstrate how $\epsilon$-PrivateSMOTE is capable of achieving competitive results in privacy risk and better predictive performance when compared to multiple traditional and state-of-the-art privacy-preservation methods, including generative adversarial networks, variational autoencoders, and differential privacy baselines. We also show how our method improves time requirements by at least a factor of 9 and is a resource-efficient solution that ensures high performance without specialised hardware.