70 citations · 138 across the 21 of their papers we have counts for
12 papers · 1 filter
Private Low-Rank Approximation for Covariance Matrices, Dyson Brownian Motion, and Eigenvalue-Gap Bounds for Gaussian Perturbations
Oren Mangoubi, Nisheeth K. Vishnoi
We consider the problem of approximating a covariance matrix with a rank- matrix under -differential privacy. We present and analyze a complex…
Faster Sampling from Log-Concave Densities over Polytopes via Efficient Linear Solvers
Oren Mangoubi, Nisheeth K. Vishnoi
We consider the problem of sampling from a log-concave distribution constrained to a polytope , where $A\in \mathbb{R}^…
Private Covariance Approximation and Eigenvalue-Gap Bounds for Complex Gaussian Perturbations
Oren Mangoubi, Nisheeth K. Vishnoi
We consider the problem of approximating a covariance matrix with a rank- matrix under -differential privacy. We present and analyze a complex…
Re-Analyze Gauss: Bounds for Private Matrix Approximation via Dyson Brownian Motion
Oren Mangoubi, Nisheeth K. Vishnoi
Given a symmetric matrix and a vector , we present new bounds on the Frobenius-distance utility of the Gaussian mechanism for approximating by a matrix whose spectrum is…
Private Matrix Approximation and Geometry of Unitary Orbits
Oren Mangoubi, Yikai Wu, Satyen Kale +2
Consider the following optimization problem: Given matrices and , maximize where varies over the unitary group . Th…
Sampling from Log-Concave Distributions over Polytopes via a Soft-Threshold Dikin Walk
Oren Mangoubi, Nisheeth K. Vishnoi
Given a Lipschitz or smooth convex function for a bounded polytope defined by inequalities, we consider the problem of sampli…
Sampling from Log-Concave Distributions with Infinity-Distance Guarantees
Oren Mangoubi, Nisheeth K. Vishnoi
For a -dimensional log-concave distribution constrained to a convex body , the problem of outputting samples from a distribution which is $\varep…
Greedy Adversarial Equilibrium: An Efficient Alternative to Nonconvex-Nonconcave Min-Max Optimization
Oren Mangoubi, Nisheeth K. Vishnoi
Min-max optimization of an objective function is an important model for robustness in an adversarial setting, with appl…
Faster polytope rounding, sampling, and volume computation via a sublinear "Ball Walk"
Oren Mangoubi, Nisheeth K. Vishnoi
We study the problem of "isotropically rounding" a polytope , that is, computing a linear transformation which makes the uniform distribution on the polytope…
Nonconvex sampling with the Metropolis-adjusted Langevin algorithm
Oren Mangoubi, Nisheeth K. Vishnoi
The Langevin Markov chain algorithms are widely deployed methods to sample from distributions in challenging high-dimensional and non-convex statistics and machine learning applica…
Dimensionally Tight Bounds for Second-Order Hamiltonian Monte Carlo
Oren Mangoubi, Nisheeth K. Vishnoi
Hamiltonian Monte Carlo (HMC) is a widely deployed method to sample from high-dimensional distributions in Statistics and Machine learning. HMC is known to run very efficiently in…
Convex Optimization with Unbounded Nonconvex Oracles using Simulated Annealing
Oren Mangoubi, Nisheeth K. Vishnoi
We consider the problem of minimizing a convex objective function when one can only evaluate its noisy approximation . Unless one assumes some structure on the noise,…