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By restricting the iterate on a nonlinear manifold, the recently proposed Riemannian optimization methods prove to be both efficient and effective in low rank tensor completion problems. However, existing methods fail to exploit the easily…

Machine Learning · Statistics 2017-02-24 Tengfei Zhou , Hui Qian , Zebang Shen , Congfu Xu

We study the convergence properties of Riemannian gradient method for solving the consensus problem (for an undirected connected graph) over the Stiefel manifold. The Stiefel manifold is a non-convex set and the standard notion of averaging…

Optimization and Control · Mathematics 2021-01-26 Shixiang Chen , Alfredo Garcia , Mingyi Hong , Shahin Shahrampour

We consider collections of Lagrangian submanifolds of a given symplectic manifold which respect uniform bounds of curvature type coming from an auxiliary Riemannian metric. We prove that, for a large class of metrics on these collections,…

Symplectic Geometry · Mathematics 2021-10-19 Jean-Philippe Chassé

Random orthogonal matrices play an important role in probability and statistics, arising in multivariate analysis, directional statistics, and models of physical systems, among other areas. Calculations involving random orthogonal matrices…

Statistics Theory · Mathematics 2018-10-09 Michael Jauch , Peter D. Hoff , David B. Dunson

We study a natural Wasserstein gradient flow on manifolds of probability distributions with discrete sample spaces. We derive the Riemannian structure for the probability simplex from the dynamical formulation of the Wasserstein distance on…

Optimization and Control · Mathematics 2021-04-19 Wuchen Li , Guido Montufar

Projected gradient descent and its Riemannian variant belong to a typical class of methods for low-rank matrix estimation. This paper proposes a new Nesterov's Accelerated Riemannian Gradient algorithm by efficient orthographic retraction…

Optimization and Control · Mathematics 2023-06-05 Hongyi Li , Zhen Peng , Chengwei Pan , Di Zhao

In this paper, we develop a new classification method for manifold-valued data in the framework of probabilistic learning vector quantization. In many classification scenarios, the data can be naturally represented by symmetric positive…

Machine Learning · Computer Science 2021-02-02 Fengzhen Tang , Haifeng Feng , Peter Tino , Bailu Si , Daxiong Ji

This paper focuses on minimizing a smooth function combined with a nonsmooth regularization term on a compact Riemannian submanifold embedded in the Euclidean space under a decentralized setting. Typically, there are two types of approaches…

Optimization and Control · Mathematics 2025-07-16 Lei Wang , Le Bao , Xin Liu

A Riemannian stochastic representation of model uncertainties in molecular dynamics is proposed. The approach relies on a reduced-order model, the projection basis of which is randomized on a subset of the Stiefel manifold characterized by…

Computational Physics · Physics 2022-10-27 Hao Zhang , Johann Guilleminot

The index of a Riemannian symmetric space is the minimal codimension of a proper totally geodesic submanifold (Onishchik, 1980). There is a conjecture by the first two authors for how to calculate the index. In this paper we give an…

Differential Geometry · Mathematics 2019-05-16 Jürgen Berndt , Carlos Olmos , Juan Sebastián Rodríguez

We propose a Riemannian version of Nesterov's Accelerated Gradient algorithm (RAGD), and show that for geodesically smooth and strongly convex problems, within a neighborhood of the minimizer whose radius depends on the condition number as…

Optimization and Control · Mathematics 2018-06-08 Hongyi Zhang , Suvrit Sra

In the context of large samples, a small number of individuals might spoil basic statistical indicators like the mean. It is difficult to detect automatically these atypical individuals, and an alternative strategy is using robust…

Machine Learning · Statistics 2023-04-04 Antoine Godichon-Baggioni , Wei Lu

In this paper, a descent method for nonsmooth multiobjective optimization problems on complete Riemannian manifolds is proposed. The objective functions are only assumed to be locally Lipschitz continuous instead of convexity used in…

Optimization and Control · Mathematics 2025-01-14 Chunming Tang , Hao He , Jinbao Jian , Miantao Chao

Consider a set of points sampled independently near a smooth compact submanifold of Euclidean space. We provide mathematically rigorous bounds on the number of sample points required to estimate both the dimension and the tangent spaces of…

Statistics Theory · Mathematics 2023-09-26 Uzu Lim , Harald Oberhauser , Vidit Nanda

We consider minimizing a nonconvex, smooth function $f$ on a Riemannian manifold $\mathcal{M}$. We show that a perturbed version of Riemannian gradient descent algorithm converges to a second-order stationary point (and hence is able to…

Optimization and Control · Mathematics 2019-06-19 Yue Sun , Nicolas Flammarion , Maryam Fazel

We study the Riemannian optimization methods on the embedded manifold of low rank matrices for the problem of matrix completion, which is about recovering a low rank matrix from its partial entries. Assume $m$ entries of an $n\times n$ rank…

Numerical Analysis · Mathematics 2016-04-12 Ke Wei , Jian-Feng Cai , Tony F. Chan , Shingyu Leung

Covariance matrices have attracted attention for machine learning applications due to their capacity to capture interesting structure in the data. The main challenge is that one needs to take into account the particular geometry of the…

Machine Learning · Computer Science 2019-09-13 Daniel Brooks , Olivier Schwander , Frederic Barbaresco , Jean-Yves Schneider , Matthieu Cord

The goal of this paper is to show how different machine learning tools on the Riemannian manifold $\mathcal{P}_d$ of Symmetric Positive Definite (SPD) matrices can be united under a probabilistic framework. For this, we will need several…

Machine Learning · Computer Science 2025-11-04 Thibault de Surrel , Florian Yger , Fabien Lotte , Sylvain Chevallier

We consider two Riemannian geometries for the manifold $\mathcal{M}(p,m\times n)$ of all $m\times n$ matrices of rank $p$. The geometries are induced on $\mathcal{M}(p,m\times n)$ by viewing it as the base manifold of the submersion…

Optimization and Control · Mathematics 2012-09-04 P. -A. Absil , Luca Amodei , Gilles Meyer

In recent years, stochastic variance reduction algorithms have attracted considerable attention for minimizing the average of a large but finite number of loss functions. This paper proposes a novel Riemannian extension of the Euclidean…

Machine Learning · Computer Science 2019-06-03 Hiroyuki Sato , Hiroyuki Kasai , Bamdev Mishra