Robustly learning mixtures of k arbitrary Gaussians

A Bakshi, I Diakonikolas, H Jia, DM Kane… - Proceedings of the 54th …, 2022 - dl.acm.org
We give a polynomial-time algorithm for the problem of robustly estimating a mixture of k
arbitrary Gaussians in ℝ d, for any fixed k, in the presence of a constant fraction of arbitrary …

Robust linear regression: Optimal rates in polynomial time

A Bakshi, A Prasad - Proceedings of the 53rd Annual ACM SIGACT …, 2021 - dl.acm.org
We obtain robust and computationally efficient estimators for learning several linear models
that achieve statistically optimal convergence rate under minimal distributional assumptions …

A moment-matching approach to testable learning and a new characterization of rademacher complexity

A Gollakota, AR Klivans, PK Kothari - Proceedings of the 55th Annual …, 2023 - dl.acm.org
A remarkable recent paper by Rubinfeld and Vasilyan (2022) initiated the study of testable
learning, where the goal is to replace hard-to-verify distributional assumptions (such as …

Algorithms approaching the threshold for semi-random planted clique

RD Buhai, PK Kothari, D Steurer - Proceedings of the 55th Annual ACM …, 2023 - dl.acm.org
We design new polynomial-time algorithms for recovering planted cliques in the semi-
random graph model introduced by Feige and Kilian. The previous best algorithms for this …

A new approach to learning linear dynamical systems

A Bakshi, A Liu, A Moitra, M Yau - Proceedings of the 55th Annual ACM …, 2023 - dl.acm.org
Linear dynamical systems are the foundational statistical model upon which control theory is
built. Both the celebrated Kalman filter and the linear quadratic regulator require knowledge …

Efficient certificates of anti-concentration beyond gaussians

A Bakshi, PK Kothari, G Rajendran… - 2024 IEEE 65th …, 2024 - ieeexplore.ieee.org
A set of high dimensional points X ={x_1,x_2,...,x_n\}⊆R^d in isotropic position is said to be
δ-anti concentrated if for every direction v, the fraction of points in X satisfying …

List decodable mean estimation in nearly linear time

Y Cherapanamjeri, S Mohanty… - 2020 IEEE 61st Annual …, 2020 - ieeexplore.ieee.org
Learning from data in the presence of outliers is a fundamental problem in statistics. Until
recently, no computationally efficient algorithms were known to compute the mean of a high …

List-decodable sparse mean estimation via difference-of-pairs filtering

I Diakonikolas, D Kane, S Karmalkar… - Advances in …, 2022 - proceedings.neurips.cc
We study the problem of list-decodable sparse mean estimation. Specifically, for a
parameter $\alpha\in (0, 1/2) $, we are given $ m $ points in $\mathbb {R}^ n $, $\lfloor\alpha …

Statistical query lower bounds for list-decodable linear regression

I Diakonikolas, D Kane, A Pensia… - Advances in Neural …, 2021 - proceedings.neurips.cc
We study the problem of list-decodable linear regression, where an adversary can corrupt a
majority of the examples. Specifically, we are given a set $ T $ of labeled examples $(x …

List-decodable covariance estimation

M Ivkov, PK Kothari - Proceedings of the 54th Annual ACM SIGACT …, 2022 - dl.acm.org
We give the first polynomial time algorithm for list-decodable covariance estimation. For any
α> 0, our algorithm takes input a sample Y⊆ d of size n≥ d poly (1/α) obtained by …