English
Related papers

Related papers: Parametric Regression on the Grassmannian

200 papers

In this work we deal with an elliptic non-linear problem, which arises naturally from Riemannian geometry. This problem has clasically been studied in the the Euclidean $n$-dimensional space and it is known as the Moser-Bernstein problem.…

Differential Geometry · Mathematics 2024-02-08 Alma L. Albujer , Jónatan Herrera , Rafael M. Rubio

Here we present a new non-parametric approach to density estimation and classification derived from theory in Radon transforms and image reconstruction. We start by constructing a "forward problem" in which the unknown density is mapped to…

Numerical Analysis · Mathematics 2024-12-20 James Webber , Erika Hussey , Eric Miller , Shuchin Aeron

The real symplectic Stiefel manifold is the manifold of symplectic bases of symplectic subspaces of a fixed dimension. It features in a large variety of applications in physics and engineering. In this work, we study this manifold with the…

Differential Geometry · Mathematics 2021-08-31 Thomas Bendokat , Ralf Zimmermann

Many machine learning applications are naturally formulated as optimization problems on Riemannian manifolds. The main idea behind Riemannian optimization is to maintain the feasibility of the variables while moving along a descent…

Optimization and Control · Mathematics 2024-06-05 Andi Han , Pratik Jawanpuria , Bamdev Mishra

We recover the Riemannian gradient of a given function defined on interior points of a Riemannian submanifold in the Euclidean space based on a sample of function evaluations at points in the submanifold. This approach is based on the…

Machine Learning · Computer Science 2023-06-06 Alvaro Almeida Gomez , Antônio J. Silva Neto , Jorge P. Zubelli

Given dense image feature correspondences of a non-rigidly moving object across multiple frames, this paper proposes an algorithm to estimate its 3D shape for each frame. To solve this problem accurately, the recent state-of-the-art…

Computer Vision and Pattern Recognition · Computer Science 2019-04-30 Suryansh Kumar

This paper introduces an online approach for identifying time-varying subspaces defined by linear dynamical systems. The approach of representing linear systems by non-parametric subspace models has received significant interest in the…

Systems and Control · Electrical Eng. & Systems 2025-12-01 András Sasfi , Alberto Padoan , Ivan Markovsky , Florian Dörfler

We construct the solution of the Riemann problem for the shallow water equations with discontinuous topography. The system under consideration is non-strictly hyperbolic and does not admit a fully conservative form, and we establish the…

Analysis of PDEs · Mathematics 2008-12-24 Philippe G. LeFloch , Mai-Duc Thanh

A main goal in the field of statistical shape analysis is to define computable and informative metrics on spaces of immersed manifolds, such as the space of curves in a Euclidean space. The approach taken in the elastic shape analysis…

Differential Geometry · Mathematics 2022-09-21 Martin Bauer , Nicolas Charon , Eric Klassen , Sebastian Kurtek , Tom Needham , Thomas Pierron

In this paper the space of images is considered as a Riemannian manifold using the metamorphosis approach, where the underlying Riemannian metric simultaneously measures the cost of image transport and intensity variation. A robust and…

Numerical Analysis · Mathematics 2015-05-28 Benjamin Berkels , Alexander Effland , Martin Rumpf

We present a Bayesian approach to identify optimal transformations that map model input points to low dimensional latent variables. The "projection" mapping consists of an orthonormal matrix that is considered a priori unknown and needs to…

Machine Learning · Statistics 2021-09-22 Panagiotis Tsilifis , Piyush Pandita , Sayan Ghosh , Valeria Andreoli , Thomas Vandeputte , Liping Wang

Gaussian variational approximation is a popular methodology to approximate posterior distributions in Bayesian inference especially in high dimensional and large data settings. To control the computational cost while being able to capture…

Machine Learning · Computer Science 2021-04-07 Bingxin Zhou , Junbin Gao , Minh-Ngoc Tran , Richard Gerlach

We study harmonic map regression, a nonparametric estimator for manifold-valued responses, that penalizes the empirical Fr\'echet risk by the Dirichlet energy. By connecting penalized regression to the theory of harmonic maps, the estimator…

Statistics Theory · Mathematics 2026-04-13 Xiaoyu Chen

Machine learning problems have an intrinsic geometric structure as central objects including a neural network's weight space and the loss function associated with a particular task can be viewed as encoding the intrinsic geometry of a given…

Machine Learning · Computer Science 2021-06-08 Guruprasad Raghavan , Matt Thomson

In image set classification, a considerable advance has been made by modeling the original image sets by second order statistics or linear subspace, which typically lie on the Riemannian manifold. Specifically, they are Symmetric Positive…

Computer Vision and Pattern Recognition · Computer Science 2018-05-31 Rui Wang , Xiao-Jun Wu , Kai-Xuan Chen , Josef Kittler

Fitting parametric models of human bodies, hands or faces to sparse input signals in an accurate, robust, and fast manner has the promise of significantly improving immersion in AR and VR scenarios. A common first step in systems that…

Computer Vision and Pattern Recognition · Computer Science 2022-07-22 Vasileios Choutas , Federica Bogo , Jingjing Shen , Julien Valentin

A central part of geometric statistics is to compute the Fr\'echet mean. This is a well-known intrinsic mean on a Riemannian manifold that minimizes the sum of squared Riemannian distances from the mean point to all other data points. The…

Machine Learning · Statistics 2025-11-07 Frederik Möbius Rygaard , Søren Hauberg , Steen Markvorsen

From optimal transport to robust dimensionality reduction, a plethora of machine learning applications can be cast into the min-max optimization problems over Riemannian manifolds. Though many min-max algorithms have been analyzed in the…

Optimization and Control · Mathematics 2022-09-29 Michael I. Jordan , Tianyi Lin , Emmanouil-Vasileios Vlatakis-Gkaragkounis

We use a new method to give conditions for the existence of a local isometric immersion of a Riemannian $n$-manifold $M$ in $\mathbb{R}^{n+k}$, for a given $n$ and $k$. These equate to the (local) existence of a $k$-tuple of scalar fields…

Differential Geometry · Mathematics 2019-09-02 Dan Gregorian Fodor

We introduce in this document a direct method allowing to solve numerically inverse type problems for linear parabolic equations. We consider the reconstruction of the full solution of the parabolic equation posed in $\Omega\times (0,T)$ -…

Optimization and Control · Mathematics 2024-02-11 Arnaud Munch , Diego Souza