Robust Sparse Mean Estimation via Sum of Squares
- URL: http://arxiv.org/abs/2206.03441v2
- Date: Fri, 5 Jul 2024 17:40:00 GMT
- Title: Robust Sparse Mean Estimation via Sum of Squares
- Authors: Ilias Diakonikolas, Daniel M. Kane, Sushrut Karmalkar, Ankit Pensia, Thanasis Pittas,
- Abstract summary: We study the problem of high-dimensional sparse mean estimation in the presence of an $epsilon$-fraction of adversarial outliers.
Our algorithms follow the Sum-of-Squares based, to algorithms approach.
- Score: 42.526664955704746
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We study the problem of high-dimensional sparse mean estimation in the presence of an $\epsilon$-fraction of adversarial outliers. Prior work obtained sample and computationally efficient algorithms for this task for identity-covariance subgaussian distributions. In this work, we develop the first efficient algorithms for robust sparse mean estimation without a priori knowledge of the covariance. For distributions on $\mathbb R^d$ with "certifiably bounded" $t$-th moments and sufficiently light tails, our algorithm achieves error of $O(\epsilon^{1-1/t})$ with sample complexity $m = (k\log(d))^{O(t)}/\epsilon^{2-2/t}$. For the special case of the Gaussian distribution, our algorithm achieves near-optimal error of $\tilde O(\epsilon)$ with sample complexity $m = O(k^4 \mathrm{polylog}(d))/\epsilon^2$. Our algorithms follow the Sum-of-Squares based, proofs to algorithms approach. We complement our upper bounds with Statistical Query and low-degree polynomial testing lower bounds, providing evidence that the sample-time-error tradeoffs achieved by our algorithms are qualitatively the best possible.
Related papers
- Robust Sparse Regression with Non-Isotropic Designs [4.964650614497048]
We develop a technique to design efficiently computable estimators for sparse linear regression in the simultaneous presence of two adversaries.
We provide a novel analysis of weighted penalized Huber loss that is suitable for heavy-tailed designs in the presence of two adversaries.
arXiv Detail & Related papers (2024-10-31T13:51:59Z) - Robust Sparse Estimation for Gaussians with Optimal Error under Huber Contamination [42.526664955704746]
We study sparse estimation tasks in Huber's contamination model with a focus on mean estimation, PCA, and linear regression.
For each of these tasks, we give the first sample and computationally efficient robust estimators with optimal error guarantees.
At the technical level, we develop a novel multidimensional filtering method in the sparse regime that may find other applications.
arXiv Detail & Related papers (2024-03-15T15:51:27Z) - A Sub-Quadratic Time Algorithm for Robust Sparse Mean Estimation [6.853165736531941]
We study the algorithmic problem of sparse mean estimation in the presence of adversarial outliers.
Our main contribution is an algorithm for robust sparse mean estimation which runs in emphsubquadratic time using $mathrmpoly(k,log d,1/epsilon)$ samples.
arXiv Detail & Related papers (2024-03-07T18:23:51Z) - Efficiently Learning One-Hidden-Layer ReLU Networks via Schur
Polynomials [50.90125395570797]
We study the problem of PAC learning a linear combination of $k$ ReLU activations under the standard Gaussian distribution on $mathbbRd$ with respect to the square loss.
Our main result is an efficient algorithm for this learning task with sample and computational complexity $(dk/epsilon)O(k)$, whereepsilon>0$ is the target accuracy.
arXiv Detail & Related papers (2023-07-24T14:37:22Z) - Near-Optimal Bounds for Learning Gaussian Halfspaces with Random
Classification Noise [50.64137465792738]
We show that any efficient SQ algorithm for the problem requires sample complexity at least $Omega(d1/2/(maxp, epsilon)2)$.
Our lower bound suggests that this quadratic dependence on $1/epsilon$ is inherent for efficient algorithms.
arXiv Detail & Related papers (2023-07-13T18:59:28Z) - Information-Computation Tradeoffs for Learning Margin Halfspaces with
Random Classification Noise [50.64137465792738]
We study the problem of PAC $gamma$-margin halfspaces with Random Classification Noise.
We establish an information-computation tradeoff suggesting an inherent gap between the sample complexity of the problem and the sample complexity of computationally efficient algorithms.
arXiv Detail & Related papers (2023-06-28T16:33:39Z) - Private estimation algorithms for stochastic block models and mixture
models [63.07482515700984]
General tools for designing efficient private estimation algorithms.
First efficient $(epsilon, delta)$-differentially private algorithm for both weak recovery and exact recovery.
arXiv Detail & Related papers (2023-01-11T09:12:28Z) - Privately Estimating a Gaussian: Efficient, Robust and Optimal [6.901744415870126]
We give efficient algorithms for privately estimating a Gaussian distribution in both pure and approximate differential privacy (DP) models.
In the pure DP setting, we give an efficient algorithm that estimates an unknown $d$-dimensional Gaussian distribution up to an arbitrary tiny total variation error.
For the special case of mean estimation, our algorithm achieves the optimal sample complexity of $widetilde O(d)$, improving on a $widetilde O(d1.5)$ bound from prior work.
arXiv Detail & Related papers (2022-12-15T18:27:39Z) - List-Decodable Mean Estimation in Nearly-PCA Time [50.79691056481693]
We study the fundamental task of list-decodable mean estimation in high dimensions.
Our algorithm runs in time $widetildeO(ndk)$ for all $k = O(sqrtd) cup Omega(d)$, where $n$ is the size of the dataset.
A variant of our algorithm has runtime $widetildeO(ndk)$ for all $k$, at the expense of an $O(sqrtlog k)$ factor in the recovery guarantee
arXiv Detail & Related papers (2020-11-19T17:21:37Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.