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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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150300450600 · Jun 202019922001200920172026
48 results for Laplacian matrix estimation

The paper derives Cramer-Rao bounds for Laplacian matrix estimation under various constraints.

problem Estimating Laplacian matrices with structural constraints and sparsity.
method Linear reparametrization and closed-form expressions for Cramer-Rao bounds tailored to Laplacian matrix estimation.
result The derived CRBs provide performance limits for Laplacian matrix estimation and are validated in various applications.

Paper proves conditions for estimating precision matrices with Laplacian constraints.

problem Estimating high-dimensional precision matrices with Laplacian constraints.
method Minimizing Stein's loss with conditions on graph connectivity and Laplacian constraints.
result High-dimensional consistency achieved with Laplacian constraints, independent of graph structure.

We provide a theoretical analysis of the representation learning problem aimed at learning the latent variables (design matrix) ΘΘ of observations YY with the knowledge of the coefficient matrix XX. The design matrix is learned under the assumption that the latent variables ΘΘ are smooth with respect to a (known) t…

2019-02-11abs ↗pdf ↗

Unified spectral clustering for sparse networks with heterogeneous degrees.

problem Efficiently detecting communities in sparse networks with varying degrees.
method Developed a parametrized regularized Laplacian matrix for spectral clustering.
result Improved parametrization accounts for network heterogeneity and community hardness.

Method estimates multiple related Gaussian distributions using Laplacian regularization.

problem Jointly estimate multiple related zero-mean Gaussian distributions.
method Laplacian regularized stratified model fitting with hyper-parameters to encourage covariance closeness.
result The method performs well, especially in low data regimes, as demonstrated in finance, radar, and weather.

GS-B3^3SE improves label shift estimation by smoothing priors on a graph.

problem Label shift adaptation when source and target distributions share conditional but not marginal probabilities.
method Graph-Smoothed Bayesian Black-Box Shift Estimator (GS-B3^3SE) places Laplacian-Gaussian priors on log-priors and confusion-matrix columns tied by a label-similarity graph.
result GS-B3^3SE produces a tractable posterior with HMC or Newton-CG schemes, proving identifiability, contraction, and robustness.

Transformers interpreted as probabilistic Laplacian Eigenmaps steps.

problem Improving transformer performance through probabilistic interpretation.
method Probabilistic Laplacian Eigenmaps model derivation and graph diffusion step.
result Subtracting identity from attention matrix improves transformer performance.

Extends spectral number variance convergence to random matrix ensembles for twisted Laplacians.

problem Spectral number variance convergence for twisted Laplacians and Dirac operators.
method Extends Rudnick's approach to Gaussian ensembles for twisted Laplacians and Dirac operators.
result Convergence to Gaussian ensembles for twisted Laplacians and Dirac operators.

New algorithms detect and estimate rank-one signals with prior directional information.

problem Detecting and estimating rank-one signals with directional prior information.
method Construct nonlinear Laplacians and examine top eigenvalues and eigenvectors.
result Nonlinear Laplacian algorithms outperform direct spectral methods for biased signals.

Enhances clustering performance with a novel high-order Laplacian matrix.

problem Limited representation capability and insufficient information exploitation in multi-view spectral clustering.
method Proposes a multi-view spectral clustering algorithm that learns a high-order optimal neighborhood Laplacian matrix.
result Improves clustering performance through enhanced representation capacity of the learned optimal Laplacian matrix.

Survey of Laplacian-based methods for data dimensionality reduction and embedding.

problem Efficiently reducing high-dimensional data to lower dimensions while preserving important features and structures.
method Laplacian-based methods including spectral clustering, Laplacian eigenmap, locality preserving projection, graph embedding, and diffusion map.
result Comprehensive overview of various optimization variants and applications of Laplacian-based techniques.

The paper tackles sparse graph learning under Laplacian-related constraints, improving upon existing methods.

problem Learning a sparse undirected graph from multivariate data under Laplacian-related constraints.
method Modifications to penalized log-likelihood approaches to enforce total positivity and lasso/adaptive lasso penalties using ADMM.
result The proposed constrained adaptive lasso approach significantly outperforms existing Laplacian-based approaches.

A checkerboard graph of a special diagram of an oriented link is made a directed, edge-weighted graph in a natural way so that a principal minor of its Laplacian matrix is a Seifert matrix of the link. Doubling and weighting the edges of the graph produces a second Laplacian matrix such that a principal minor is an Ale…

2018-09-18abs ↗pdf ↗

Graphs are fundamental mathematical structures used in various fields to represent data, signals and processes. In this paper, we propose a novel framework for learning/estimating graphs from data. The proposed framework includes (i) formulation of various graph learning problems, (ii) their probabilistic interpretatio…

2016-11-16abs ↗pdf ↗

The spectral geometry of mesh matrices of graphs is explored, leading to new formulas and eigenvalue estimates.

problem Understanding the spectral properties of mesh matrices of graphs.
method Definition and study of mesh matrices, introduction of mesh Laplacian, derivation of characteristic polynomial formulas.
result Mesh Laplacian eigenvalues are all real and greater than or equal to 1, with a smallest positive eigenvalue estimated.

The 1\ell_1-norm fails to produce sparse solutions in Laplacian constrained graphical models, leading to a complete graph.

problem Learning a sparse graph under Laplacian constrained Gaussian graphical models.
method Introduced a nonconvex sparsity penalty and proposed a new estimator using a sequence of weighted 1\ell_1-norm penalized sub-problems. Developed a projected gradient descent algorithm with linear convergence rate.
result The proposed estimator can recover the edges correctly with high probability and is effective on both synthetic and real-world data sets.

S2MAM improves semi-supervised learning by selecting relevant variables and updating similarity metrics.

problem Joint learning from labeled and unlabeled data with geometric structure.
method Bilevel optimization scheme for automatic variable selection and similarity matrix update.
result The proposed S2MAM achieves robust and interpretable predictions.

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.

Study on signed graphs with random signs, focusing on community detection.

problem Community detection in signed stochastic block models.
method Strong concentration inequalities for adjacency and Laplacian matrices, applied to signed Laplacian matrix.
result The sign of the first eigenvector of the Laplacian matrix defines a weakly consistent estimator for balanced community detection.

In this paper, we introduce a new directed graphical model from Gaussian data: the Gaussian graphical interaction model (GGIM). The development of this model comes from considering stationary Gaussian processes on graphs, and leveraging the equations between the resulting steady-state covariance matrix and the Laplacia…

2019-06-19abs ↗pdf ↗

The smallest eigenvalues and the associated eigenvectors (i.e., eigenpairs) of a graph Laplacian matrix have been widely used for spectral clustering and community detection. However, in real-life applications the number of clusters or communities (say, KK) is generally unknown a-priori. Consequently, the majority of …

2015-12-23abs ↗pdf ↗

Novel Haar-Laplacian for directed graphs enhances spectral graph applications.

problem Lack of suitable Laplacian for directed graphs in spectral graph theory.
method Inspired by Haar-like transformation, introduces a Hermitian matrix preserving direction and weight.
result HaarNet outperforms in weight prediction and denoising on directed graphs.

Many important problems are characterized by the eigenvalues of a large matrix. For example, the difficulty of many optimization problems, such as those arising from the fitting of large models in statistics and machine learning, can be investigated via the spectrum of the Hessian of the empirical loss function. Networ…

2018-02-09abs ↗pdf ↗

Dual regularized graph Laplacian improves spectral clustering for community detection.

problem Detecting clusters in networks with improved spectral clustering methods.
method Proposes dual regularized graph Laplacian for three spectral clustering approaches.
result Theoretical analysis shows DRSC and DRSLIM yield stable consistent community detection.

The paper develops a method to sparsify magnetic Laplacians using multi-type spanning forests.

problem Sparsifying magnetic Laplacians for large and dense graphs.
method Sampling multi-type spanning forests using a determinantal point process.
result The method provides statistical guarantees for estimating the connection Laplacian.

The high-order relations between the content in social media sharing platforms are frequently modeled by a hypergraph. Either hypergraph Laplacian matrix or the adjacency matrix is a big matrix. Randomized algorithms are used for low-rank factorizations in order to approximately decompose and eventually invert such big…

2019-08-22abs ↗pdf ↗

Many problems in machine learning can be expressed by means of a graph with nodes representing training samples and edges representing the relationship between samples in terms of similarity, temporal proximity, or label information. Graphs can in turn be represented by matrices. A special example is the Laplacian matr…

2019-09-18abs ↗pdf ↗

The potential of recovering the topology of a grid using solely publicly available market data is explored here. In contemporary whole-sale electricity markets, real-time prices are typically determined by solving the network-constrained economic dispatch problem. Under a linear DC model, locational marginal prices (LM…

2013-12-02abs ↗pdf ↗

Using Roelcke formula for the Green function, we explicitly construct a basis in the kernel of the adjoint Laplacian on a compact polyhedral surface XX and compute the SS-matrix of XX at the zero value of the spectral parameter. We apply these results to study various self-adjoint extensions of a symmetric Laplacian…

2019-02-08abs ↗pdf ↗

Following Hartigan, a cluster is defined as a connected component of the t-level set of the underlying density, i.e., the set of points for which the density is greater than t. A clustering algorithm which combines a density estimate with spectral clustering techniques is proposed. Our algorithm is composed of two step…

2010-02-11abs ↗pdf ↗

Manifold learning and dimensionality reduction techniques are ubiquitous in science and engineering, but can be computationally expensive procedures when applied to large data sets or when similarities are expensive to compute. To date, little work has been done to investigate the tradeoff between computational resourc…

2016-03-12abs ↗pdf ↗

The paper proves spectral convergence rates for graph Laplacian to manifold Laplace-Beltrami operator.

problem Spectral convergence of graph Laplacian to manifold Laplace-Beltrami operator.
method Analysis of Dirichlet form convergence and construction of approximate eigenfunctions via manifold heat kernel.
result Proves spectral convergence rates for Gaussian kernelized graph Laplacian.

Paper interprets UMAP and t-SNE as probabilistic MAP inference.

problem Understanding and interpreting UMAP and t-SNE.
method Interprets UMAP and t-SNE as MAP inference methods corresponding to a probabilistic model of the graph Laplacian.
result Shows UMAP and t-SNE can be understood as probabilistic inference methods.

We introduce a general framework for estimation of inverse covariance, or precision, matrices from heterogeneous populations. The proposed framework uses a Laplacian shrinkage penalty to encourage similarity among estimates from disparate, but related, subpopulations, while allowing for differences among matrices. We p…

2016-01-02abs ↗pdf ↗