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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.

168,932 papers · 148 categories

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216432648864 · Jun 202019922001200920172026
48 results for density optimization

Optimizes sliding window approach for tracking Gaussian densities.

problem Improving tracking performance of Gaussian density estimation.
method Theoretical analysis of sliding window Gaussian Kernel Density Estimators.
result Empirical evidence shows improved tracking performance with optimal weight sequence.

TAKDE optimizes kernel density estimation for real-time dynamic processes.

problem Real-time density estimation in applications like computer vision and signal processing.
method Derives asymptotic mean integrated squared error (AMISE) upper bound for 'sliding window' kernel density estimator and proposes TAKDE as a novel, theoretically optimal estimator.
result TAKDE outperforms other dynamic density estimators in terms of test log-likelihood and runtime.

Paper proposes a new approach to optimal transport for vector and matrix densities.

problem Optimal transport for vector and matrix densities with positivity and action transitivity constraints.
method Gauge-theoretic approach using semi-direct product groups of diffeomorphisms and gauge transformations.
result Bures-type metrics on semi-direct product groups relate to Wasserstein-type metrics on vector and matrix densities via Riemannian submersions.

Optimizes kernel density ratios for better predictions and information measures.

problem Improving accuracy of kernel density estimates for density ratios.
method Derives an optimal weight function using calculus of variations.
result Reduces bias in kernel density estimates, leading to improved prediction posteriors and information-theoretic measures.

Study online monotone density estimation with expert aggregation and log-optimal calibration.

problem Online monotone density estimation and log-optimal calibration.
method Proposed two online estimators: Grenander estimator and expert aggregation estimator.
result Online estimators achieve O(n1/3)O(n^{1/3}) cumulative log-likelihood gap and nlogn\sqrt{n\log{n}} pathwise regret bound.

We address the following problem: given two smooth densities on a manifold, find an optimal diffeomorphism that transforms one density into the other. Our framework builds on connections between the Fisher-Rao information metric on the space of probability densities and right-invariant metrics on the infinite-dimension…

2015-01-29abs ↗pdf ↗

The paper analyzes kNN density estimation's convergence rates under different conditions.

problem Analyzing convergence rates of kNN density estimation under bounded and unbounded support conditions.
method Examined two cases: bounded support with known and unknown support sets, and unbounded support with smooth density function.
result kNN density estimation is minimax optimal under certain conditions and better than kernel density estimation in some cases.

This paper proposes a new method for automatically selecting the optimal kernel bandwidth in density estimation.

problem The challenge of selecting the optimal kernel bandwidth in unsupervised density estimation.
method The approach uses a topology-based loss function for automated bandwidth selection.
result Demonstrates the potential of the topology-based approach across different dimensions.

Unified framework for implicit generative models with theoretical guarantees.

problem Learning implicit generative models with theoretical guarantees.
method Integrating optimal transport, numerical ODE, density-ratio estimation, and deep neural networks.
result Unified framework with theoretical guarantees for implicit generative learning.

BO method improved by density-ratio estimation for better efficiency and scalability.

problem Limitations in Bayesian optimization due to analytical tractability of predictive models.
method Reformulated Bayesian optimization by casting expected improvement as a binary classification problem.
result Improved efficiency and scalability of Bayesian optimization.

This study optimizes covariate density and propensity score for efficient ATE estimation.

problem Efficiently estimating average treatment effects (ATEs) with minimal variance.
method Adaptive experiment optimizing both covariate density and propensity score.
result Proposed method minimizes the semiparametric efficiency bound for ATE estimation.

Optimizes spectral density estimation for stationary and nonstationary processes.

problem Estimating spectral density of time series with complex structure.
method Optimally adaptive Bayesian spectral density estimation using smoothing spline covariance structure.
result Optimal eigendecomposition provides superior performance compared to alternative covariance functions.

Stable and consistent model alignment for language models without assuming human preference models.

problem Lack of statistical consistency in existing alignment methods.
method Relative density ratio optimization between preferred and mixture of preferred and non-preferred data distributions.
result Our approach achieves statistical consistency and stability, providing tighter convergence guarantees.

We propose a Fourier-based approach for optimization of several clustering algorithms. Mathematically, clusters data can be described by a density function represented by the Dirac mixture distribution. The density function can be smoothed by applying the Fourier transform and a Gaussian filter. The determination of th…

2019-04-29abs ↗pdf ↗

New method uses random projections to estimate densities and modes efficiently.

problem Estimating densities and modes from sparse representations.
method Expand-and-sparsify representations followed by linear function and mode recovery algorithms.
result Optimal rates for density and mode estimation achieved.

Flow Matching improves statistical guarantees through kernel density estimation.

problem Improving statistical guarantees for generative models.
method Connecting Flow Matching to kernel density estimation and verifying optimal rates of convergence.
result Flow Matching achieves optimal rates up to logarithmic factors for large networks and on lower-dimensional manifolds.

Paper introduces a new anomaly detection framework combining density estimation and deep learning.

problem Detecting anomalies in data with varying dimensions.
method Two versions: shallow approach using adaptive Fourier features and density matrices; deep approach using autoencoder.
result Both methods achieve comparable or superior performance compared to state-of-the-art methods.

Paper tackles unbounded density ratio estimation for covariate shift adaptation.

problem Understudied challenge in statistical learning: unbounded density ratios.
method Three-step estimation method: relative density ratio, truncation, and transformation.
result Established rigorous convergence guarantees for density ratio and regression estimators.

Direct Density Ratio Optimization aligns LLMs with human preferences without assuming specific models.

problem Statistical inconsistency in aligning LLMs with human preferences.
method Direct Density Ratio Optimization (DDRO) estimates density ratio directly.
result DDRO is statistically consistent, converging to true human preferences as data grows.

BOKE optimizes expensive functions with reduced computational costs.

problem High computational cost of Gaussian process-based Bayesian optimization.
method Kernel regression and density-based exploration integrated into confidence bounds.
result BOKE achieves global convergence and superior computational efficiency.

Develops a new test for comparing two groups' densities, showing minimax optimality.

problem Comparing probability densities between two groups.
method Probabilistic tensor product smoothing spline framework for joint density modeling; penalized likelihood ratio test for interaction testing.
result Proposed test is minimax optimal and outperforms conventional approaches.

The variational autoencoder (VAE) is a powerful generative model that can estimate the probability of a data point by using latent variables. In the VAE, the posterior of the latent variable given the data point is regularized by the prior of the latent variable using Kullback Leibler (KL) divergence. Although the stan…

2018-09-14abs ↗pdf ↗

A new method selects a representative subsample for efficient kernel density estimation.

problem Selecting a representative subsample without model assumptions.
method Optimal transport techniques for model-free subsampling with an efficient algorithm.
result The selected subsample can be used for efficient density estimation with derived convergence rates and optimal bandwidth.

Polynomial-time algorithm estimates edge density of random graphs with privacy and robustness.

problem Estimating edge density of random graphs while maintaining privacy and robustness.
method Sum-of-squares algorithm for robust edge density estimation and reduction from privacy to robustness.
result Optimal error rate up to logarithmic factors, matching theoretical lower bounds.

A new method for generating time-dependent densities efficiently.

problem Computational difficulties in deep learning for temporal density modeling.
method Projection-based optimal transport and transport splines.
result The method is highly competitive with state-of-the-art normalizing flows.

Paper establishes a density formula for diffusion models, linking target density to score function.

problem Lack of theoretical foundation for optimizing DDPMs using ELBO.
method Developed a density formula for continuous-time diffusion processes, revealing the connection between target density and score function.
result The minimizer of the ELBO objective for DDPMs nearly coincides with the true objective, providing a theoretical foundation.

New method minimizes robust density power-based divergences for general parametric densities.

problem Computational complexity of minimizing DPD for general parametric densities.
method Stochastic approach to minimize DPD for general parametric density models.
result Proposed method can be applied to minimize other density power-based γ-divergences.

Optimal testing for densities under local differential privacy constraints.

problem Testing goodness-of-fit for densities under privacy constraints.
method Estimation of quadratic distance and minimax separation rates.
result First minimax optimal test under local differential privacy constraints.

Proposes log density gradient to improve reinforcement learning sample complexity.

problem Residual error in gradient estimation in policy gradient methods.
method Log density gradient method to correct residual error, using state-action discounted distributional formulation.
result Min-max optimization method to approximate log density gradient with on-policy samples, achieving sample complexity of m1/2m^{-1/2}.