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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.

169,341 papers · 148 categories

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22446587 · May 202619922001200920182026
48 results for Orthogonal Filters

Scalable approach for high-dimensional dynamical systems with noise filtering and parameter estimation.

problem Noise filtering and parameter estimation for high-dimensional dynamical systems.
method Flexible latent factor model with orthogonal factor loading matrix and closed-form parameter estimation.
result Substantial acceleration and higher accuracy compared to alternatives.

A new ML-based filter improves data assimilation for nonlinear systems.

problem Improving data assimilation for nonlinear systems using ensemble methods.
method Developed a machine learning-based conditional mean filter (ML-EnCMF) integrating ANN and linear functions.
result ML-EnCMF outperforms EnKF and likelihood-based EnCMF in nonlinear systems.

New method differentiates square-root Kalman filters robustly.

problem Gradient calculation issues in square-root Kalman filters.
method Closed-form chain rule derived from Gramian identity, resolves non-orthogonal and rank-deficient issues.
result Robust automatic differentiation for Kalman filters, resolving numerical stability and gradient issues.

Bayesian Markowitz portfolio problem shows entropy regularization is ineffective.

problem Entropy regularization in Bayesian Markowitz portfolio optimization.
method Combines continuous-time Bayesian filtering with stochastic policy optimization.
result Entropy regularization does not accelerate learning of unknown drift.

The article uses Karhunen-Loève decomposition and Filtered Historical Simulation to manage volatility risk in interest rate options.

problem Managing volatility risk in interest rate options with changing implied volatilities.
method Karhunen-Loève decomposition and Filtered Historical Simulation.
result The projections on principal components provide a more accurate prediction of Value at Risk (VaR).

Designing a photometric system to best fulfil a set of scientific goals is a complex task, demanding a compromise between conflicting requirements and subject to various constraints. A specific example is the determination of stellar astrophysical parameters (APs) - effective temperature, metallicity etc. - across a wi…

2004-02-25abs ↗pdf ↗

ORFit trains models on streaming data with one pass, minimizing memory and computational costs.

problem Training large models on a stream of data without retraining on previous data.
method Orthogonal Recursive Fitting (ORFit) using orthogonal gradient descent and recursive least-squares.
result ORFit updates parameters orthogonally to past gradients, leading to efficient memory and computational usage.

New CAOL framework learns diverse convolutional filters for improved signal recovery.

problem Memory limitations in patch-domain approaches for learning kernels from large datasets.
method Convolutional Analysis Operator Learning (CAOL) framework with BPEG-M method.
result CAOL significantly accelerates convergence and improves reconstruction quality.

New approach to portfolio optimization shows entropy regularization is ineffective.

problem Entropy regularization in mean-variance portfolio optimization under drift uncertainty.
method Combining Bayesian filtering and stochastic policy optimization.
result Entropy regularization does not accelerate learning about unknown drift.

ABO extends RLS for online learning in non-stationary time-series, improving accuracy and speed.

problem Online learning in non-stationary time-series with overparameterized models.
method QR-based exponentially weighted RLS algorithm with orthogonal-triangular updates.
result ABO maintains bounded residuals and stable condition numbers while achieving speed improvements.

SVD training reduces DNN rank and computation load without SVD per step.

problem High memory and computational load in deep neural networks.
method Explicitly achieves low-rank DNNs during training without SVD per step, using orthogonality regularization and sparsity-inducing regularizers.
result Significantly reduces DNN rank and computation load compared to existing methods.

Derives optimal dynamic trading strategies under Gaussian assumptions.

problem Understanding and optimizing dynamic trading strategies in finance.
method Assumes Gaussian returns and dynamic weights, derives closed-form expressions for strategy returns moments.
result Positive skewness and excess kurtosis are essential for positive Sharpe dynamic strategies.

A-MMSE uses attention to learn efficient OFDM channel estimation.

problem Accurate OFDM channel estimation requires second-order statistics, which are hard to obtain in practice.
method A-MMSE is a model-based DNN framework that learns linear MMSE filters via Attention Transformer, reducing inference complexity.
result A-MMSE outperforms other methods in normalized MSE across various SNR conditions.

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.

Study isotropy groups for complex orthogonal and skew-symmetric matrices.

problem Understanding isotropy subgroups of orthogonal similarity transformations.
method Analysis of group structure of nonsingular block matrices.
result Group structure of isotropy subgroups related to block Toeplitz matrices.

Orthogonal Random Features reduce kernel approximation error and speed up computation.

problem Gaussian kernel approximation error reduction and speed up computation.
method Replacing random Gaussian matrix with a scaled random orthogonal matrix, and using structured discrete orthogonal matrices.
result Significantly decreases kernel approximation error and reduces computation time from O(d2)\mathcal{O}(d^2) to O(dlogd)\mathcal{O}(d \log d).

OPT framework improves neural network generalization by learning an orthogonal transformation.

problem Improving neural network generalization.
method Orthogonal over-parameterized training (OPT) framework that minimizes hyperspherical energy.
result OPT framework provably minimizes hyperspherical energy and improves empirical generalization.

The paper studies surfaces in a bounded domain with orthogonal boundaries and proves curvature estimates.

problem Estimating the area of surfaces with orthogonal boundaries in a bounded domain.
method Weak formulation of orthogonality for curvature varifolds, classification of vanishing curvature varifolds.
result Existence of an orthogonal 2-varifold that minimizes L2L^2 curvature in the integer rectifiable class.

Orthogonal random features approximate a Bessel kernel, offering sharper bounds than random Fourier features.

problem Approximating Gaussian kernel efficiently for large datasets.
method Use of Haar orthogonal matrices to construct orthogonal random features and analyze their bias and variance.
result Orthogonal random features approximate a Bessel kernel, not the Gaussian kernel, with sharper bounds.

Paper proves rigidity of spherical ring patterns on surfaces.

problem Proving rigidity of spherical orthogonal ring patterns on closed surfaces.
method Modification of combinatorial total geodesic curvature and variational principles.
result Rigidity of spherical orthogonal ring patterns on closed surfaces proved.

Proposes FOAGP for efficient orthogonal effect decomposition of black-box computer experiments.

problem Challenges in sensitivity analysis of black-box computer experiments with complex, nonlinear functional outputs.
method Functional-output orthogonal additive Gaussian process (FOAGP) with conditional orthogonality constraint.
result Demonstrates effectiveness in orthogonal effect decomposition and variance decomposition through simulations and real-world application.

Novel prior for orthogonal functions improves functional component estimation.

problem Improving orthogonality in functional principal component analysis.
method Sequential adaptive priors for orthogonal functions using hierarchical conditionally normal distributions.
result Proposed prior leads to nearly orthogonal posterior estimates.

Method constructs orthogonal curvilinear coordinates in constant curvature spaces.

problem Creating orthogonal coordinates in spaces of constant curvature.
method Modification of Krichever's method for Euclidean space, applied to constant curvature spaces.
result Examples of orthogonal coordinate systems on the sphere and hyperbolic plane constructed.

We study the Chern-Simons partition function of orthogonal quantum group invariants, and propose a new orthogonal Labastida-Mariño-Ooguri-Vafa conjecture as well as degree conjecture for free energy associated to the orthogonal Chern-Simons partition function. We prove the degree conjecture and some interesting cases o…

2010-07-09abs ↗pdf ↗

A Clifford algebra model for M"obius geometry is presented. The notion of Ribaucour pairs of orthogonal systems in arbitrary dimensions is introduced, and the structure equations for adapted frames are derived. These equations are discretized and the geometry of the occuring discrete nets and sphere congruences is disc…

1998-02-27abs ↗pdf ↗

DONUT improves treatment effect estimation by enforcing orthogonality constraints.

problem Estimating treatment effects from observational data is challenging due to unobserved outcomes.
method DONUT uses a regularization framework that formalizes unconfoundedness as orthogonality, leading to deep orthogonal networks.
result DONUT outperforms state-of-the-art methods in estimating average treatment effects.

New convergence guarantees for learning with unknown nuisance parameters.

problem Learning problems with unknown nuisance parameters.
method Stochastic gradient optimization with Neyman orthogonality and approximately orthogonalized updates.
result Stochastic gradient algorithms can converge under conditions of nuisance parameters.

Orthogonal initialization does not speed up training in ultra-wide neural networks.

problem Exploring the effect of orthogonal initialization on training speed in deep neural networks.
method Study of neural tangent kernel dynamics in FCNs and CNNs with orthogonal initialization.
result The NTK of orthogonally-initialized networks remains constant during training, suggesting no speedup in the NTK regime.

MuonEq improves training of matrix-valued parameters by rebalancing momentum before orthogonalization.

problem Training matrix-valued parameters with orthogonalized-update optimizers like Muon.
method MuonEq introduces three lightweight pre-orthogonalization equilibration schemes: two-sided row/column normalization (RC), row normalization (R), and column normalization (C).
result Row/column normalization acts as a zeroth-order surrogate for whitening and improves the geometry seen by orthogonalization.

A new algorithm POGO optimizes thousands of orthogonal matrices efficiently.

problem Optimizing thousands of orthogonal constraints at scale is computationally expensive.
method Revisits Landing algorithm, uses modern adaptive optimizers, reduces hyperparameters.
result POGO optimizes thousands of orthogonal matrices in minutes, outperforming alternatives.

The paper finds at least N orthogonal Finsler geodesic chords in a disk-like manifold.

problem Existence and multiplicity of orthogonal Finsler geodesic chords in a disk-like manifold.
method Study of Finsler geodesic chords under reversibility assumption.
result At least N orthogonal Finsler geodesic chords found in a disk-like manifold.