Provable Privacy with Non-Private Pre-Processing
<|reference_start|>Provable Privacy with Non-Private Pre-Processing: When analysing Differentially Private (DP) machine learning pipelines, the potential privacy cost of data-dependent pre-processing is frequently overlooked in privacy accounting. In this work, we propose a general framework to evaluate the additional privacy cost incurred by non-private data-dependent pre-processing algorithms. Our framework establishes upper bounds on the overall privacy guarantees by utilising two new technical notions: a variant of DP termed Smooth DP and the bounded sensitivity of the pre-processing algorithms. In addition to the generic framework, we provide explicit overall privacy guarantees for multiple data-dependent pre-processing algorithms, such as data imputation, quantization, deduplication and PCA, when used in combination with several DP algorithms. Notably, this framework is also simple to implement, allowing direct integration into existing DP pipelines.<|reference_end|>
@article{hu2024provable,
    title={Provable Privacy with Non-Private Pre-Processing},
    author={Yaxi Hu, Amartya Sanyal, Bernhard Sch"olkopf},
    journal={arXiv preprint arXiv:2403.13041},
    year={2024},
    archivePrefix={arXiv},
    eprint={2403.13041},
    primaryClass={cs.CR cs.AI cs.LG stat.ML}
}