Research
On-device research index

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.

168,742 papers · 148 categories

Trend · papers per month

25.0%50.0%75.0%100.0% · Sep 199219922001200920172026
48 results for generalized matrix mean

Proposes a new regularizer for semi-supervised learning on multilayer graphs.

problem Semi-supervised learning on multilayer graphs with labeled and unlabeled data.
method Generalized matrix mean regularizer and matrix-free numerical scheme.
result The regularizer outperforms state-of-the-art methods numerically.

A new method for distributed PCA using matrix β-mean.

problem Efficiently aggregating PCA results across multiple machines with reduced computational overhead.
method Proposes a novel DPCA method that incorporates eigenvalue information using the matrix β-mean.
result The matrix β-mean method improves robustness and stability of eigenvector ordering.

The original k-means clustering method works only if the exact vectors representing the data points are known. Therefore calculating the distances from the centroids needs vector operations, since the average of abstract data points is undefined. Existing algorithms can be extended for those cases when the sole input i…

2013-03-24abs ↗pdf ↗

We show that the objective function of conventional k-means clustering can be expressed as the Frobenius norm of the difference of a data matrix and a low rank approximation of that data matrix. In short, we show that k-means clustering is a matrix factorization problem. These notes are meant as a reference and intende…

2015-12-23abs ↗pdf ↗

Paper develops a method to construct confidence regions for model parameters using batch means method.

problem Constructing confidence regions for model parameters in stochastic gradient descent.
method Batch means method to cancel out covariance matrix, using Polyak-Ruppert averaging.
result Established process-level functional central limit theorem for stochastic gradient descent estimators.

New method for matrix completion using Kronecker product approximation.

problem Matrix completion with low Kronecker rank structure.
method Alternative matrix representation using Kronecker product, identification through mean squared error and modified cross-validation.
result Consistency of the method under suitable signal-to-noise ratio conditions.

Novel mean estimation method under user-level differential privacy reduces noise in continual mean estimates.

problem Maintaining accurate running mean estimates under user-level differential privacy.
method Developed a novel mean estimation specific factorization under approximate differential privacy.
result Achieved asymptotically lower mean-squared error bounds in continual mean estimation.

Signed graphs encode positive (attractive) and negative (repulsive) relations between nodes. We extend spectral clustering to signed graphs via the one-parameter family of Signed Power Mean Laplacians, defined as the matrix power mean of normalized standard and signless Laplacians of positive and negative edges. We pro…

2019-05-15abs ↗pdf ↗

A clustering algorithm uses the left Gram matrix for high dimensional data.

problem Clustering high dimensional data with many features and few objects.
method The algorithm uses the normalized left Gram matrix G = XX'/P to cluster objects based on row means.
result The algorithm provides the most accurate cluster configuration more than twice as often as competitors.

This paper solves the convergence problem for estimating MGGD parameters with a convex formulation.

problem Establishing convergence properties for estimating MGGD parameters with unknown mean and precision matrix.
method Proposes a convex formulation with well-established convergence properties for robust estimation in noisy scenarios.
result Demonstrates improved accuracy in precision and covariance matrix estimation compared to existing methods.

Binary data matrices can represent many types of data such as social networks, votes, or gene expression. In some cases, the analysis of binary matrices can be tackled with nonnegative matrix factorization (NMF), where the observed data matrix is approximated by the product of two smaller nonnegative matrices. In this …

2018-12-17abs ↗pdf ↗

Kernel clustering algorithm improved for large datasets using incomplete Cholesky factorization.

problem Large memory usage in kernel-based clustering for large-scale datasets.
method Approximate the kernel matrix using incomplete Cholesky factorization and apply linear kk-means clustering.
result The proposed method achieves similar performance to kernel kk-means clustering but handles large-scale datasets efficiently.

Study of metrics on positive-definite matrices from power potential, linking to power means.

problem Understanding metrics on positive-definite matrices derived from power potential.
method Explicit expressions for geodesics and distance function derived from Hessian of power potential.
result Geodesics and distance function converge to weighted matrix geometric mean as β tends to zero.

We generalize the recently discovered relationship between JT gravity and double-scaled random matrix theory to the case that the boundary theory may have time-reversal symmetry and may have fermions with or without supersymmetry. The matching between variants of JT gravity and matrix ensembles depends on the assumed s…

2019-07-07abs ↗pdf ↗

Paper proposes a method to break symmetries in Bayesian matrix factorization.

problem Symmetries in posterior distribution reduce MCMC sampling efficiency.
method Modification to Gaussian prior mean and covariance to break symmetries.
result Breaking symmetries leads to lower autocorrelation and reconstruction errors.

Efficiently reduces rank of non-negative matrices with quadratic time complexity.

problem Efficiently reducing the rank of non-negative matrices.
method Formulated rank reduction as a mean-field approximation using a log-linear model.
result Optimal solution for minimizing KL divergence can be computed in closed form.

Corrected whitening restores orthogonality in high-dimensional spherical Gaussian mixtures.

problem In high-dimensional data, standard whitening fails to preserve orthogonality of mixture means.
method Derived exact limits for whitened means dot products using random matrix theory, constructed a corrected whitening matrix.
result Corrected whitening allows for improved estimation of spherical Gaussian mixtures in the large-dimensional regime.

Enhances ROM simulation for multivariate systems with exact Kollo skewness.

problem Modeling multivariate systems with high dimensions and specific higher moments.
method Extends Random Orthogonal Matrix simulation to match target Kollo skewness.
result Established conditions and developed a general approach for constructing admissible values.

We use the explicit relation between genus filtrated ss-loop means of the Gaussian matrix model and terms of the genus expansion of the Kontsevich--Penner matrix model (KPMM), which is the generating function for volumes of discretized (open) moduli spaces Mg,sdiscM_{g,s}^{disc} (discrete volumes), to express Gaussian means…

2015-12-31abs ↗pdf ↗

In this paper we derive the optimal linear shrinkage estimator for the high-dimensional mean vector using random matrix theory. The results are obtained under the assumption that both the dimension pp and the sample size nn tend to infinity in such a way that p/nc(0,)p/n \to c\in(0,\infty). Under weak conditions imposed on…

2016-10-28abs ↗pdf ↗

In this work, the possibility of clustering correlated random variables was examined, both because of their mutual similarity and because of their similarity to the principal components. The k-means algorithm and spectral algorithms were used for clustering. For spectral methods, the similarity matrix was both the matr…

2019-09-07abs ↗pdf ↗

Principal components analysis (PCA) is a well-known technique for approximating a tabular data set by a low rank matrix. Here, we extend the idea of PCA to handle arbitrary data sets consisting of numerical, Boolean, categorical, ordinal, and other data types. This framework encompasses many well known techniques in da…

2014-10-01abs ↗pdf ↗

Since Li and Yau obtained the gradient estimate for the heat equation, related estimates have been extensively studied. With additional curvature assumptions, matrix estimates that generalize such estimates have been discovered for various time-dependent settings, including the heat equation on a Kähler manifold, Ricci…

2017-04-25abs ↗pdf ↗

Paper analyzes VI for location-scale families, proving robustness guarantees for mean and correlation recovery.

problem Misspecification in VI for intractable target densities.
method Variational inference on location-scale families with symmetries.
result VI recovers mean and correlation matrix under specific symmetries.

Real-world data such as digital images, MRI scans and electroencephalography signals are naturally represented as matrices with structural information. Most existing classifiers aim to capture these structures by regularizing the regression matrix to be low-rank or sparse. Some other methodologies introduce factorizati…

2018-07-02abs ↗pdf ↗

Investigates portfolio optimization with and without gearing constraints.

problem Improving portfolio weights for better alignment with expected returns.
method Extends the alpha-weight angle bound to include gearing constraints and uses theoretical arguments and simulations.
result Equally weighted portfolios are not preferable to mean-variance portfolios even with poor forecast ability and a badly conditioned covariance matrix.

Method selects number of communities in weighted networks.

problem Selecting the number of communities in weighted networks.
method Proposes a novel weighted DCSBM and uses a sequential testing framework with spectral clustering and matrix scaling.
result Method is consistent in estimating the true number of communities under mild conditions.

Paper improves matrix-valued data classification using nonparametric LDA.

problem Classification of matrix-valued data in neuroimaging and signal processing.
method Nonparametric LDA based on NPMLE for vectorized and scaled matrices.
result Improves classification performance across various data structures.

The paper computes an approximation to the sample Frechet mean of graph sets using spectral information.

problem Characterizing the location of a set of graphs in a metric space.
method The Frechet mean is computed for sets of large graphs using the pseudometric defined by the norm between eigenvalues of adjacency matrices.
result An algorithm to approximate the sample Frechet mean of undirected unweighted graphs is described.