activity
20152026
most citedOptimality and Sub-optimality of PCA I: Spiked Random Matrix Models

78 citations · 436 across the 33 of their papers we have counts for

collaborators

41 papers

math.ST2026

From Weak to Strong Testing in Gaussian Models

Ansh Nagda, Alexander S. Wein

We study the computational complexity of hypothesis testing in the spiked Wigner model, a prototypical model for detecting low-rank structure in a large random matrix. Below the "B…

cs.DS2026

Beyond Frequency Marching: Orbit Recovery in Dihedral and Projected Multireference Alignment

Tait Weicht, Alexander S. Wein

Multireference alignment (MRA) is the task of recovering a hidden "signal" vector, given many noisy copies that have been cyclically shifted by unknown offsets. This task belongs t…

math.ST2024

Statistical inference of a ranked community in a directed graph

Dmitriy Kunisky, Daniel A. Spielman, Alexander S. Wein +1

We study the problem of detecting or recovering a planted ranked subgraph from a directed graph, an analog for directed graphs of the well-studied planted dense subgraph model. We…

math.ST2024★ 1 cited

Tensor cumulants for statistical inference on invariant distributions

Dmitriy Kunisky, Cristopher Moore, Alexander S. Wein

Many problems in high-dimensional statistics appear to have a statistical-computational gap: a range of values of the signal-to-noise ratio where inference is information-theoretic…

math.ST2024★ 1 cited

Information-Theoretic Thresholds for Planted Dense Cycles

Cheng Mao, Alexander S. Wein, Shenduo Zhang

We study a random graph model for small-world networks which are ubiquitous in social and biological sciences. In this model, a dense cycle of expected bandwidth , representin…

math.ST2023

Precise Error Rates for Computationally Efficient Testing

Ankur Moitra, Alexander S. Wein

We revisit the fundamental question of simple-versus-simple hypothesis testing with an eye towards computational complexity, as the statistically optimal likelihood ratio test is o…

cs.DS2023★ 1 cited

Detection of Dense Subhypergraphs by Low-Degree Polynomials

Abhishek Dhawan, Cheng Mao, Alexander S. Wein

Detection of a planted dense subgraph in a random graph is a fundamental statistical and computational problem that has been extensively studied in recent years. We study a hypergr…

cs.CC2023★ 1 cited

Is Planted Coloring Easier than Planted Clique?

Pravesh K. Kothari, Santosh S. Vempala, Alexander S. Wein +1

We study the computational complexity of two related problems: recovering a planted -coloring in , and finding efficiently verifiable witnesses of non--colorability…

math.ST2023★ 2 cited

Detection-Recovery Gap for Planted Dense Cycles

Cheng Mao, Alexander S. Wein, Shenduo Zhang

Planted dense cycles are a type of latent structure that appears in many applications, such as small-world networks in social sciences and sequence assembly in computational biolog…

math.ST2022

Is it easier to count communities than find them?

Cynthia Rush, Fiona Skerman, Alexander S. Wein +1

Random graph models with community structure have been studied extensively in the literature. For both the problems of detecting and recovering community structure, an interesting…

math.ST2022★ 6 cited

Equivalence of Approximate Message Passing and Low-Degree Polynomials in Rank-One Matrix Estimation

Andrea Montanari, Alexander S. Wein

We consider the problem of estimating an unknown parameter vector , given noisy observations ${\boldsymbol Y} = {\boldsymbol θ}{\boldsymbol θ}^{\to…

cs.CC2022★ 7 cited

Average-Case Complexity of Tensor Decomposition for Low-Degree Polynomials

Alexander S. Wein

Suppose we are given an -dimensional order-3 symmetric tensor that is the sum of random rank-1 terms. The problem of recovering the rank-1…

cs.DS2022★ 1 cited

Near-optimal fitting of ellipsoids to random points

Aaron Potechin, Paxton Turner, Prayaag Venkat +1

Given independent standard Gaussian points in dimension , for what values of does there exist with high probability an origin-symmetric ellipsoid tha…

stat.ML2022★ 6 cited

Statistical and Computational Phase Transitions in Group Testing

Amin Coja-Oghlan, Oliver Gebhard, Max Hahn-Klimroth +2

We study the group testing problem where the goal is to identify a set of k infected individuals carrying a rare disease within a population of size n, based on the outcomes of poo…

math.ST2022★ 11 cited

The Franz-Parisi Criterion and Computational Trade-offs in High Dimensional Statistics

Afonso S. Bandeira, Ahmed El Alaoui, Samuel B. Hopkins +3

Many high-dimensional statistical inference problems are believed to possess inherent computational hardness. Various frameworks have been proposed to give rigorous evidence for su…

cs.LG2022★ 2 cited

Lattice-Based Methods Surpass Sum-of-Squares in Clustering

Ilias Zadik, Min Jae Song, Alexander S. Wein +1

Clustering is a fundamental primitive in unsupervised learning which gives rise to a rich class of computationally-challenging inference tasks. In this work, we focus on the canoni…

cs.CC2021★ 4 cited

Circuit Lower Bounds for the p-Spin Optimization Problem

David Gamarnik, Aukosh Jagannath, Alexander S. Wein

We consider the problem of finding a near ground state of a -spin model with Rademacher couplings by means of a low-depth circuit. As a direct extension of the authors' recent w…

math.ST2021★ 7 cited

Optimal Spectral Recovery of a Planted Vector in a Subspace

Cheng Mao, Alexander S. Wein

Recovering a planted vector in an -dimensional random subspace of is a generic task related to many problems in machine learning and statistics, such as dicti…

cs.DS2020★ 1 cited

Average-Case Integrality Gap for Non-Negative Principal Component Analysis

Afonso S. Bandeira, Dmitriy Kunisky, Alexander S. Wein

Montanari and Richard (2015) asked whether a natural semidefinite programming (SDP) relaxation can effectively optimize over $\|\mathbf{x}\…

cs.CC2020

Optimal Low-Degree Hardness of Maximum Independent Set

Alexander S. Wein

We study the algorithmic task of finding a large independent set in a sparse Erdős-Rényi random graph with vertices and average degree . The maximum independent set is known…

cs.CC2020★ 13 cited

Spectral Planting and the Hardness of Refuting Cuts, Colorability, and Communities in Random Graphs

Afonso S. Bandeira, Jess Banks, Dmitriy Kunisky +2

We study the problem of efficiently refuting the k-colorability of a graph, or equivalently certifying a lower bound on its chromatic number. We give formal evidence of average-cas…

math.ST2020★ 50 cited

Computational Barriers to Estimation from Low-Degree Polynomials

Tselil Schramm, Alexander S. Wein

One fundamental goal of high-dimensional statistics is to detect or recover planted structure (such as a low-rank matrix) hidden in noisy data. A growing body of work studies low-d…

math.PR2020★ 8 cited

Free Energy Wells and Overlap Gap Property in Sparse PCA

Gérard Ben Arous, Alexander S. Wein, Ilias Zadik

We study a variant of the sparse PCA (principal component analysis) problem in the "hard" regime, where the inference task is possible yet no polynomial-time algorithm is known to…

math.ST2020★ 5 cited

The Average-Case Time Complexity of Certifying the Restricted Isometry Property

Yunzi Ding, Dmitriy Kunisky, Alexander S. Wein +1

In compressed sensing, the restricted isometry property (RIP) on sensing matrices (where ) guarantees efficient reconstruction of sparse vectors. A matrix has t…