# Private Algorithms for Stochastic Saddle Points and Variational Inequalities: Beyond Euclidean Geometry

arXiv: https://arxiv.org/abs/2411.05198 · HTML: https://mlsanity.com/paper/2411.05198/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 22 of its 42 references that are in the map.
- First posted on arXiv 7 Nov 2024.

## Builds on (most cited first, 22 of 22)

- [Deep Learning with Differential Privacy](https://mlsanity.com/paper/1607.00133/) (2016)
- [A Reductions Approach to Fair Classification](https://mlsanity.com/paper/1803.02453/) (2018)
- [Private Stochastic Convex Optimization with Optimal Rates](https://mlsanity.com/paper/1908.09970/) (2019)
- [Private Stochastic Convex Optimization: Optimal Rates in Linear Time](https://mlsanity.com/paper/2005.04763/) (2020)
- [Fairness risk measures](https://mlsanity.com/paper/1901.08665/) (2019)
- [Private Stochastic Convex Optimization: Optimal Rates in ℓ1 Geometry](https://mlsanity.com/paper/2103.01516/) (2021)
- [Stochastic Variance Reduction Methods for Saddle-Point Problems](https://mlsanity.com/paper/1605.06398/) (2016)
- [How To Make the Gradients Small Stochastically: Even Faster Convex and Nonconvex SGD](https://mlsanity.com/paper/1801.02982/) (2018)
- [Non-Euclidean Differentially Private Stochastic Convex Optimization: Optimal Rates in Linear Time](https://mlsanity.com/paper/2103.01278/) (2021)
- [Stability and Generalization of Stochastic Gradient Methods for Minimax Problems](https://mlsanity.com/paper/2105.03793/) (2021)
- [Stochastic Primal-Dual Coordinate Method for Regularized Empirical Risk Minimization](https://mlsanity.com/paper/1409.3257/) (2014)
- [Generalization Bounds for Stochastic Saddle Point Problems](https://mlsanity.com/paper/2006.02067/) (2020)
- [Differentially Private SGDA for Minimax Problems](https://mlsanity.com/paper/2201.09046/) (2022)
- [Bring Your Own Algorithm for Optimal Differentially Private Stochastic Minimax Optimization](https://mlsanity.com/paper/2206.00363/) (2022)
- [Fast Distributionally Robust Learning with Variance Reduced Min-Max Optimization](https://mlsanity.com/paper/2104.13326/) (2021)
- [Optimal Algorithms for Differentially Private Stochastic Monotone Variational Inequalities and Saddle-Point Problems](https://mlsanity.com/paper/2104.02988/) (2021)
- [Near-Optimal Algorithms for Group Distributionally Robust Optimization and Beyond](https://mlsanity.com/paper/2212.13669/) (2022)
- [What is a Good Metric to Study Generalization of Minimax Learners?](https://mlsanity.com/paper/2206.04502/) (2022)
- [Differentially Private Algorithms for the Stochastic Saddle Point Problem with Optimal Rates for the Strong Gap](https://mlsanity.com/paper/2302.12909/) (2023)
- [Differentially Private Worst-group Risk Minimization](https://mlsanity.com/paper/2402.19437/) (2024)
- [Mirror Descent Algorithms with Nearly Dimension-Independent Rates for Differentially-Private Stochastic Saddle-Point Problems](https://mlsanity.com/paper/2403.02912/) (2024)
- [Beyond Minimax Rates in Group Distributionally Robust Optimization via a Novel Notion of Sparsity](https://mlsanity.com/paper/2410.00690/) (2024)

## Built on by (most cited first, 2 of 2)

- [On the Gradient Complexity of Private Optimization with Private Oracles](https://mlsanity.com/paper/2511.13999/) (2025)
- [Private Rate-Constrained Optimization with Applications to Fair Learning](https://mlsanity.com/paper/2505.22703/) (2025)

## Abstract (arXiv)

In this work, we conduct a systematic study of stochastic saddle point problems (SSP) and stochastic variational inequalities (SVI) under the constraint of (ε,δ)-differential privacy (DP) in both Euclidean and non-Euclidean setups. We first consider Lipschitz convex-concave SSPs in the ℓp/ℓq setup, p,q∈[1,2]. Here, we obtain a bound of tildeObig(frac1√n + frac√dnεbig) on the strong SP-gap, where n is the number of samples and d is the dimension. This rate is nearly optimal for any p,q∈[1,2]. Without additional assumptions, such as smoothness or linearity requirements, prior work under DP has only obtained this rate when p=q=2 (i.e., only in the Euclidean setup). Further, existing algorithms have each only been shown to work for specific settings of p and q and under certain assumptions on the loss and the feasible set, whereas we provide a general algorithm for DP SSPs whenever p,q∈[1,2]. Our result is obtained via a novel analysis of the recursive regularization algorithm. In particular, we develop new tools for analyzing generalization, which may be of independent interest. Next, we turn our attention towards SVIs with a monotone, bounded and Lipschitz operator and consider ℓp-setups, p∈[1,2]. Here, we provide the first analysis which obtains a bound on the strong VI-gap of tildeObig(frac1√n + frac√dnεbig). For p-1=Omega(1), this rate is near optimal due to existing lower bounds. To obtain this result, we develop a modified version of recursive regularization. Our analysis builds on the techniques we develop for SSPs as well as employing additional novel components which handle difficulties arising from adapting the recursive regularization framework to SVIs.
