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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.

169,051 papers · 148 categories

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3.6%7.1%10.7%14.3% · Oct 199219922001200920182026
48 results for Subspace Identification

Bayesian methods reduce variance in subspace identification for small data sets.

problem High variance in traditional subspace identification methods for large models or small sample sizes.
method Investigation of Bayesian estimation solutions (regularized and shrinkage estimators) for subspace identification.
result Bayesian estimators reduce estimation risk by up to 40% compared to traditional methods.

We propose a conjugate gradient type optimization technique for the computation of the Karcher mean on the set of complex linear subspaces of fixed dimension, modeled by the so-called Grassmannian. The identification of the Grassmannian with Hermitian projection matrices allows an accessible introduction of the geometr…

2012-09-14abs ↗pdf ↗

Projective DP-SGD reduces privacy error by identifying low-dimensional gradient subspaces.

problem Differentially private SGD's error rate scales with model's dimensionality, problematic for over-parameterized models.
method Projective DP-SGD, projecting noisy gradients to a low-dimensional subspace identified from a public dataset.
result The method reduces the dependence on model dimensionality, improving accuracy in high privacy regimes.

Paper analyzes and improves GPSP algorithm for block sparse signal recovery.

problem Recovering block sparse signals from noisy data.
method Group Projected Subspace Pursuit (GPSP) with convergence analysis and feature selection criteria.
result GPSP exactly recovers true block sparse signals under certain conditions.

Robust PCA, the problem of PCA in the presence of outliers has been extensively investigated in the last few years. Here we focus on Robust PCA in the column sparse outlier model. The existing methods for column sparse outlier model assumes either the knowledge of the dimension of the lower dimensional subspace or the …

2018-04-13abs ↗pdf ↗

In this paper we consider the problem of group invariant subspace clustering where the data is assumed to come from a union of group-invariant subspaces of a vector space, i.e. subspaces which are invariant with respect to action of a given group. Algebraically, such group-invariant subspaces are also referred to as su…

2015-10-15abs ↗pdf ↗

Active sampling selects few points for accurate model reduction of high-fidelity systems.

problem Efficiently identify dominant subspaces for model reduction of large training sets.
method Proposes an active sampling strategy to select a few points from the training set to estimate dominant subspaces accurately.
result Active sampling can provide 17x speed-up without sacrificing accuracy.

Paper recovers multi-subspace matrices from permuted data.

problem Recovering a multi-subspace matrix from permuted data with corrupted columns.
method Four-stage algorithm pipeline: outlier identification, subspace reconstruction, outlier classification, unsupervised sensing.
result The pipeline provides theoretical guarantees for reliable multi-subspace matrix recovery.

New algorithm identifies outliers in PCA without needing parameters.

problem Robust PCA with unknown outlier fraction and subspace dimension.
method Non-iterative, parameter-free method for structured and unstructured outliers.
result Analytical guarantees and performance comparison with existing methods.

In this paper we present deterministic conditions for success of sparse subspace clustering (SSC) under missing data, when data is assumed to come from a Union of Subspaces (UoS) model. We consider two algorithms, which are variants of SSC with entry-wise zero-filling that differ in terms of the optimization problems u…

2016-07-11abs ↗pdf ↗

This paper considers the problem of completing a matrix with many missing entries under the assumption that the columns of the matrix belong to a union of multiple low-rank subspaces. This generalizes the standard low-rank matrix completion problem to situations in which the matrix rank can be quite high or even full r…

2011-12-23abs ↗pdf ↗

In this paper we present deterministic analysis of sufficient conditions for sparse subspace clustering under missing data, when data is assumed to come from a Union of Subspaces (UoS) model. In this context we consider two cases, namely Case I when all the points are sampled at the same co-ordinates, and Case II when …

2016-04-15abs ↗pdf ↗

The paper analyzes system identification with finite data.

problem Recovering system parameters and Kalman filter gain from noisy output measurements.
method Subspace identification algorithm, finite number of output samples, random matrix theory, self-normalized martingales, SVD robustness.
result Estimation errors decrease with a rate of 1/\sqrt{N}, valid even for marginally stable systems.

New method identifies latent components in PNL mixtures without strong assumptions.

problem Identifying latent components in PNL mixtures under unknown nonlinear functions.
method Carefully designed UML criterion to identify a null space associated with the mixing system.
result Identification/removal of unknown nonlinearity under minimal conditions.

EOMR improves regression accuracy in chaotic systems by identifying relevant feature subsets and subspaces.

problem Learning relevant feature subsets and subspaces in nonstationary and nonlinear regression problems.
method Jointly identifies relevant feature subsets and subspaces using Entropy-Optimal Manifold Regression (EOMR).
result EOMR achieves orders of magnitude better prediction accuracy than state-of-the-art AI and ML tools.

Paper proves noise-tolerant SSC using greedy methods under coherence conditions.

problem Proving noise-tolerant SSC using greedy methods under coherence conditions.
method Derives coherence-based sufficient conditions for correct neighbor identification using MP/OMP in the presence of bounded noise.
result MP/OMP succeed in identifying correct neighbors under certain noise levels, leading to higher clustering accuracy.

Sparse Bayesian learning algorithm for estimating interaction kernels in Motsch-Tadmor model.

problem Data-driven identification of asymmetric interaction kernels in the Motsch-Tadmor model.
method Variational framework reformulating kernel identification as a subspace identification problem; sparse Bayesian learning algorithm with informative priors.
result Accurate, robust, and interpretable estimation of interaction kernels across various noise levels and data regimes.

ISOKANN learns collective variables and effective dynamics for metastable transitions.

problem Understanding metastable transitions in complex molecular systems.
method Integrates Koopman operators with neural networks to extract CVs and effective dynamics.
result Reconstructs coarse-grained kinetics and reproduces transition times across barriers.

Paper models Alzheimer's disease using genotypic, phenotypic, and cognitive data.

problem Early detection and risk factor identification for Alzheimer's disease.
method Probabilistic generative subspace learning from multi-view medical data.
result Proposes a method to model Alzheimer's disease that combines genotypic, phenotypic, and cognitive data.

Unified framework for disentangled representations using mechanistic independence.

problem Identifiability of disentangled latent factors under statistical dependencies.
method Introduces mechanistic independence to characterize latent factors by their actions on observed variables, proposing various independence criteria.
result Establishes conditions for identifiability of latent subspaces without statistical assumptions.

The paper develops Kalman filters for unknown systems with sample complexity bounds.

problem Designing Kalman filters for systems with unknown parameters and noise.
method Combines system identification with Kalman filter design, ensuring robustness and sub-optimality guarantees.
result Proves sub-optimality guarantees for both Certainty Equivalent and robust Kalman filters with sample complexity bounds.

Over the past years Robust PCA has been established as a standard tool for reliable low-rank approximation of matrices in the presence of outliers. Recently, the Robust PCA approach via nuclear norm minimization has been extended to matrices with linear structures which appear in applications such as system identificat…

2015-06-12abs ↗pdf ↗

We identify and approximate weights of two-layer neural networks from few samples.

problem Identifying and approximating weights of two-layer neural networks from limited data.
method Active sampling of finite difference approximations to Hessians, solving robust nonlinear programs, and gradient descent.
result Stable recovery of network weights under verifiable conditions.

Proposes methods to identify and estimate counterfactual distributions with confounding.

problem Estimating counterfactual distributions in the presence of confounding.
method Nonparametric identification and semiparametric estimation using conditional copulas and machine learning.
result Valid inference for individual-level effects and nonparametric identifiability of latent confounding subspace.

Using the L^2 norm of the Higgs field as a Morse function, we study the moduli spaces of U(p,q)-Higgs bundles over a Riemann surface. We require that the genus of the surface be at least two, but place no constraints on (p,q). A key step is the identification of the function's local minima as moduli spaces of holomorph…

2002-11-27abs ↗pdf ↗

Paper uses random projection to preserve subspace structure for efficient data analysis.

problem Efficiently analyzing data with low-dimensional structure.
method Compressed Subspace Learning (CSL) framework based on Johnson-Lindenstrauss property.
result Random projection preserves the UoS structure of data, enabling efficient analysis.

Detects missing tensor signals in a KS subspace with high probability.

problem Detecting tensor signals with many missing entities in a KS subspace.
method Projecting the signal onto the KS subspace and bounding residual energy.
result Reliable detection is possible if the missing signal cardinality exceeds KS subspace dimensions.

Study on vector fields on Lie groups reveals surprising algebraic coincidences.

problem Characterizing vector fields on Lie groups with Riemannian metrics.
method Algebraic and geometric analysis of left-invariant vector fields on nilpotent Lie groups.
result Spaces of Killing, one-harmonic, and conformal vector fields coincide with the center of the Lie algebra on nilpotent Lie groups.