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arXiv research

A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,657 papers · 148 categories

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13263952 · May 202619922001200920172026
48 results for Orthogonal eigenvectors

The paper tackles learning symmetries in data without expert knowledge.

problem Learning symmetries in data from raw data without prior knowledge.
method Develops methods to select eigenvectors for orthogonal symmetries and compares their effectiveness.
result The problem of learning symmetries is as hard as the graph automorphism problem in the worst case, but can be simplified with certain restrictions.

SpecNet2 improves spectral embedding without orthogonalization, achieving better performance and efficiency.

problem Improving spectral embedding methods for better performance and efficiency.
method Optimizes an equivalent objective of the eigen-problem without orthogonalization, allowing separate row and column sampling.
result Local and global convergence of the new objective using batch-based gradient descent is proven, and improved performance and efficiency are demonstrated on simulated and image datasets.

The study extends Jacobi-orthogonality to indefinite scalar product spaces.

problem Generalizing Jacobi-orthogonality to indefinite scalar product spaces.
method Comparing principles, investigating tensor relations, proving properties.
result Every quasi-Clifford tensor is Jacobi-orthogonal; certain tensors are Jacobi-dual or Osserman.

Spectral methods achieve near-optimal performance in orthogonal and permutation group synchronization.

problem Recovering group elements from pairwise measurements in computer vision.
method Spectral methods applied with the leave-one-out technique.
result Near-optimal performance bounds for orthogonal and permutation group synchronization established.

Sign equivariant networks improve model expressiveness for spectral geometric learning.

problem Limited expressiveness of sign invariant models for tasks like graph link prediction.
method Developed sign equivariant neural network architectures based on new analytic sign equivariant polynomials.
result Sign equivariant models achieve theoretical benefits in spectral geometric learning tasks.

We propose a general framework to study the stability of the subspace spanned by PP consecutive eigenvectors of a generic symmetric matrix H0{\bf H}_0, when a small perturbation is added. This problem is relevant in various contexts, including quantum dissipation (H0{\bf H}_0 is then the Hamiltonian) and risk control …

2011-08-22abs ↗pdf ↗

In this paper, we apply tools from the random matrix theory (RMT) to estimates of correlations across volatility of various assets in the S&P 500. The volatility inputs are estimated by modeling price fluctuations as GARCH(1,1) process. The corresponding correlation matrix is constructed. It is found that the distribut…

2013-10-06abs ↗pdf ↗

In many applications, one has side information, e.g., labels that are provided in a semi-supervised manner, about a specific target region of a large data set, and one wants to perform machine learning and data analysis tasks "nearby" that prespecified target region. For example, one might be interested in the clusteri…

2013-04-28abs ↗pdf ↗

Random matrix ensembles yield uniform distributions on manifolds.

problem Understanding distributions of vectors in random matrix ensembles.
method Analyzing eigenvalues, singular values, and Autonne-Takagi vectors of various random matrix ensembles.
result Uniform distributions on specific manifolds for different types of random matrix ensembles.

Algorithm estimates principal eigenvector with adaptive sensing, improving over non-adaptive methods.

problem Estimating principal eigenvector with limited scalar measurements.
method Compressed variant of Oja's algorithm using two adaptive measurements per sample.
result Convergence rate of O(λ1λ2d2/(Δ2t))\mathcal{O}(λ_1λ_2 d^2 / (Δ^2 t)) after tt iterations, matching information-theoretic lower bound.

We propose a general framework to study the stability of the subspace spanned by PP consecutive eigenvectors of a generic symmetric matrix H0{\bf H}_0, when a small perturbation is added. This problem is relevant in various contexts, including quantum dissipation (H0{\bf H}_0 is then the Hamiltonian) and financial ris…

2012-03-28abs ↗pdf ↗

We analyze cross-correlations between price fluctuations of different stocks using methods of random matrix theory (RMT). Using two large databases, we calculate cross-correlation matrices C of returns constructed from (i) 30-min returns of 1000 US stocks for the 2-yr period 1994--95 (ii) 30-min returns of 881 US stock…

2001-08-01abs ↗pdf ↗

A new classifier uses weighted orthogonal regression for robust classification with limited data.

problem Challenges in classification with insufficient training data.
method Exploits intrinsic structure of data through Eigen components with specific weights determined by eigenvalues.
result Robust learning in classification problems with limited data.

I introduce Forecastable Component Analysis (ForeCA), a novel dimension reduction technique for temporally dependent signals. Based on a new forecastability measure, ForeCA finds an optimal transformation to separate a multivariate time series into a forecastable and an orthogonal white noise space. I present a converg…

2012-05-21abs ↗pdf ↗

Introduces tunable basis functions for Gaussian processes.

problem Reduces computational complexity in Gaussian process approximations.
method Introduces tunable, local, and bounded basis functions for kernel approximation.
result Demonstrates superior performance compared to state-of-the-art methods, especially with poorly chosen kernel functions.

A new method for sparse PCA using orthogonal rotations and soft-thresholding.

problem Sparse PCA with a new basis using orthogonal rotations.
method Initialize with leading principal components, apply kimeskk imes k orthogonal rotation, and soft-threshold the rotated components.
result The proposed method is more stable and explains more variance compared to alternatives.

Latent variable models with hidden binary units appear in various applications. Learning such models, in particular in the presence of noise, is a challenging computational problem. In this paper we propose a novel spectral approach to this problem, based on the eigenvectors of both the second order moment matrix and t…

2018-02-27abs ↗pdf ↗

New method identifies structural parameters without assuming uncorrelated errors.

problem Identifying structural parameters in simultaneous equation models.
method Exploits higher-order cumulant restrictions, not requiring uncorrelated errors.
result Simple diagonality condition on hhth-order cumulants identifies structural parameter matrix.

Machine learning models perform better with location coordinates alone, not Moran Eigenvectors.

problem Improving machine learning models for spatial data.
method Examined Moran Eigenvectors as additional spatial features in machine learning models using synthetic datasets.
result Machine learning models using only location coordinates achieve better accuracies than eigenvector-based approaches.

Paper addresses eigenvector perturbation in small eigen-gap scenarios.

problem Fine-grained behavior of eigenvectors in the presence of small eigen-gaps.
method Develops de-biased estimators for linear functions of an unknown eigenvector.
result Achieves minimax lower bounds for a family of scenarios, even with small eigen-gaps.

A new methodology has been introduced to clean the correlation matrix of single stocks returns based on a constrained principal component analysis using financial data. Portfolios were introduced, namely "Fundamental Maximum Variance Portfolios", to capture in an optimal way the risks defined by financial criteria ("Bo…

2020-01-24abs ↗pdf ↗

This work improves disentanglement in latent space models without sacrificing generation quality.

problem Trade-off between disentanglement and generation quality in latent space models.
method Manifold optimization with a sum of autoencoder and PCA reconstruction errors, on the Stiefel manifold.
result Improves disentanglement without sacrificing generation quality.

In spectral clustering, one defines a similarity matrix for a collection of data points, transforms the matrix to get the Laplacian matrix, finds the eigenvectors of the Laplacian matrix, and obtains a partition of the data using the leading eigenvectors. The last step is sometimes referred to as rounding, where one ne…

2012-10-16abs ↗pdf ↗

We study distributed computing of the truncated singular value decomposition problem. We develop an algorithm that we call \texttt{LocalPower} for improving communication efficiency. Specifically, we uniformly partition the dataset among mm nodes and alternate between multiple (precisely pp) local power iterations an…

2020-02-19abs ↗pdf ↗

New metric tensor field on symmetric matrices simplifies eigenvector computation.

problem Complex eigenvector computation for 2x2 symmetric matrices.
method Introducing a metric tensor field on the space of symmetric matrices, resulting in a curved manifold.
result Parallel transport simplifies eigenvector computation for one-parameter families of matrices.

Spectral clustering performance depends on eigenvector fluctuations, shown to be Gaussian.

problem Predicting the performance of spectral clustering.
method General spike random matrix model and rotational invariance of noise.
result Fluctuations of eigenvector entries are Gaussian in large-dimensional regime.

New neural architectures invariant to sign flips and basis symmetries for graph representation learning.

problem Learning invariant graph representations from eigenvectors.
method SignNet and BasisNet neural architectures that are invariant to sign flips and basis symmetries.
result Proven to be universal, approximating any continuous function of eigenvectors with desired invariances.

A special Kähler-Ricci potential on a Kähler manifold is any nonconstant CC^\infty function ττ such that J(τ)J(\nablaτ) is a Killing vector field and, at every point with dτ0dτ\ne 0, all nonzero tangent vectors orthogonal to τ\nablaτ and J(τ)J(\nablaτ) are eigenvectors of both dτ\nabla dτ and the Ricci tensor. For instan…

2002-04-27abs ↗pdf ↗

New theory for eigenvectors of generalized Laplacian matrices, addressing dependency issues.

problem Dependency in random matrix theory hinders eigenvector analysis for latent embeddings.
method Introduces generalized Laplacian matrices and a new asymptotic theory framework.
result Established asymptotic normalities for spiked eigenvectors and eigenvalues.