activity
20232025
collaborators

10 papers

cs.LG2025

Differentially Private Bilevel Optimization: Efficient Algorithms with Near-Optimal Rates

Andrew Lowy, Daogao Liu

Bilevel optimization, in which one optimization problem is nested inside another, underlies many machine learning applications with a hierarchical structure -- such as meta-learnin…

cs.DS2025

Private Geometric Median in Nearly-Linear Time

Syamantak Kumar, Daogao Liu, Kevin Tian +1

Estimating the geometric median of a dataset is a robust counterpart to mean estimation, and is a fundamental problem in computational geometry. Recently, [HSU24] gave an $(\vareps…

cs.LG2024

Faster Algorithms for User-Level Private Stochastic Convex Optimization

Andrew Lowy, Daogao Liu, Hilal Asi

We study private stochastic convex optimization (SCO) under user-level differential privacy (DP) constraints. In this setting, there are users (e.g., cell phones), each possess…

cs.LG2024

Adaptive Batch Size for Privately Finding Second-Order Stationary Points

Daogao Liu, Kunal Talwar

There is a gap between finding a first-order stationary point (FOSP) and a second-order stationary point (SOSP) under differential privacy constraints, and it remains unclear wheth…

cs.LG2024

Improved Sample Complexity for Private Nonsmooth Nonconvex Optimization

Guy Kornowski, Daogao Liu, Kunal Talwar

We study differentially private (DP) optimization algorithms for stochastic and empirical objectives which are neither smooth nor convex, and propose methods that return a Goldstei…

cs.DS2024

Private Stochastic Convex Optimization with Heavy Tails: Near-Optimality from Simple Reductions

Hilal Asi, Daogao Liu, Kevin Tian

We study the problem of differentially private stochastic convex optimization (DP-SCO) with heavy-tailed gradients, where we assume a -moment bound on the Lipschitz…

cs.LG2024

Private Online Learning via Lazy Algorithms

Hilal Asi, Tomer Koren, Daogao Liu +1

We study the problem of private online learning, specifically, online prediction from experts (OPE) and online convex optimization (OCO). We propose a new transformation that trans…

cs.LG2024

Private Gradient Descent for Linear Regression: Tighter Error Bounds and Instance-Specific Uncertainty Estimation

Gavin Brown, Krishnamurthy Dvijotham, Georgina Evans +3

We provide an improved analysis of standard differentially private gradient descent for linear regression under the squared error loss. Under modest assumptions on the input, we ch…

stat.ME2023

Fast Rerandomization via the BRAIN

Jiuyao Lu, Daogao Liu, Zhanran Lin +1

Randomized experiments are a crucial tool for causal inference in many different fields. Rerandomization addresses any covariate imbalance in such experiments by resampling treatme…

cs.LG2023

User-level Differentially Private Stochastic Convex Optimization: Efficient Algorithms with Optimal Rates

Hilal Asi, Daogao Liu

We study differentially private stochastic convex optimization (DP-SCO) under user-level privacy, where each user may hold multiple data items. Existing work for user-level DP-SCO…