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.

169,341 papers · 148 categories

Trend · papers per month

92184276368 · Jun 202019922001200920182026
48 results for Log-density gradient

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}.

Improved VI with Price's gradient estimator for target log-density.

problem Approximating target distributions from unnormalized log-densities.
method Stochastic gradient-based variational inference with Price's gradient estimator.
result Identifies Price's gradient as the key to WVI's superior performance.

Novel NGCA algorithm finds non-Gaussian subspace without iterative steps.

problem Identifying a linear subspace with non-Gaussian projected data.
method Log-density gradient estimation for eigenvalue decomposition.
result Identified subspace converges to true subspace at optimal rate.

Paper proposes a new method for robust modal regression.

problem Estimating the global mode of conditional density functions robustly.
method Directly approximates the gradient of modal regression risk using kernelized and neural-network-based log-density derivative estimators.
result Proposed methods achieve superior performance on various datasets.

A new metric tensor improves Riemann manifold Monte Carlo for Bayesian models.

problem Improving sampling efficiency in Bayesian hierarchical models.
method Metric tensor derived from log-density gradient covariance matrices.
result Metric tensors enhance sampling for complex Bayesian models.

Residual Flows improve flow-based models for density estimation.

problem Density estimation using flow-based models with biased log-density estimates.
method Proposed a Russian roulette estimator for unbiased log-density estimation and used an alternative infinite series for gradient calculation. Improved invertible residual blocks with activation functions avoiding derivative saturation and generalized Lipschitz condition to induced mixed norms.
result Residual Flows achieve state-of-the-art performance on density estimation and outperform coupling block networks in joint generative and discriminative modeling.

BBVI converges nearly dimensionally independent for log-concave targets.

problem Efficiently optimizing variational parameters in high-dimensional spaces.
method Proved convergence rate of BBVI with reparametrization gradient for log-concave targets.
result BBVI converges with nearly independent dimension dependence for log-concave targets.

Pathfinder uses quasi-Newton optimization for variational inference.

problem Approximating complex posterior distributions efficiently.
method Pathfinder combines quasi-Newton optimization with variational methods to approximate log densities.
result Pathfinder produces draws with lower KL divergence than ADVI and comparable to HMC, requiring fewer evaluations.

Paper improves sampling from smooth, log-concave densities with inaccurate gradients.

problem Sampling from smooth, log-concave densities with inaccurate gradient evaluations.
method Approximate sampling using discretizations of the Langevin diffusion with optimized step sizes and various gradient approximations.
result Improved guarantees on sampling error, including logarithmic improvements and nonasymptotic bounds for second-order methods.

Reparameterization trick yields more accurate gradient estimates in variational inference.

problem Improving gradient estimates in variational inference.
method Idealized analysis of mean-field Gaussian approximations and quadratic log densities.
result Marginal variances of reparameterization gradient are smaller than score function gradient.

Smart Bayes integrates generative and discriminative features for improved classification.

problem Improving classification performance by combining generative and discriminative modeling.
method Integrates generative likelihood-ratio features into a logistic-regression-style classifier.
result Often outperforms logistic regression and Naive Bayes in simulations and real data.

Proposes a deep neural network for multi-dimensional functional data classification.

problem Classifying multi-dimensional functional data with non-Gaussian distributions.
method Trains a deep neural network on the principle components of the training data.
result FDNN achieves minimax optimality when log density ratio has a locally connected modular structure.

Establishes conditions for geometric ergodicity in Hamiltonian Monte Carlo.

problem Conditions for geometric ergodicity in Hamiltonian Monte Carlo.
method Analyzes Markov chains with position-independent and position-dependent integration times.
result Recovery of geometric ergodicity in Hamiltonian Monte Carlo for broader tail behaviors.

Normalizing flow regression approximates posterior distributions without additional sampling.

problem Bayesian inference with computationally expensive likelihood evaluations.
method Normalizing flow regression (NFR) for offline inference.
result NFR yields a tractable posterior approximation through regression on existing log-density evaluations.

Improved score matching methods for estimating score functions and Hessians without high dimensionality.

problem Estimating score functions and Hessians efficiently in high-dimensional data.
method Implicit score matching and denoising score matching, leveraging Gagliardo-Nirenberg inequalities.
result Achieves convergence rates similar to denoising score matching and estimates Hessians without dimensionality issues.

Estimates Gaussian location model with ridge regularization, comparing variational and spectral methods.

problem Estimating parameters in Gaussian location model with regularization.
method Ridge-regularized log-density-ratio estimation, variational and spectral approaches.
result Regularized variational estimator has lower risk with many observations, spectral estimator with fewer observations.

Statistical analysis of algorithm unrolling for inverse problems.

problem Designing deep neural networks to solve inverse problems efficiently.
method Analysis of gradient descent network (GDN) unrolling depth and statistical performance.
result The optimal statistical performance of GDNs requires unrolling depth of order log(n)/log(ρ_n^-1), where ρ_n is the convergence rate.

New method estimates model discrepancy without sampling for unnormalized models.

problem Evaluating and training unnormalized density models efficiently.
method Estimate Stein discrepancy using neural network parameterized vector function.
result Method outperforms existing goodness-of-fit tests and training methods.

A new sampling method reduces computational cost for high-dimensional log-concave distributions.

problem High computational cost of ULMC in high dimensions.
method Random Coordinate ULMC (RC-ULMC) selects a single coordinate per iteration.
result RC-ULMC is cheaper than classical ULMC, especially in highly skewed and high-dimensional problems.

ASVGD accelerates SVGD for efficient sampling from Gaussian targets.

problem Efficient sampling from Gaussian distributions using SVGD.
method Accelerated gradient flow in a metric space of probability densities, including momentum and Wasserstein regularization.
result ASVGD achieves optimal convergence rate for Gaussian targets, independent of covariance.

New research shows input-gradients can be manipulated without changing model's core function, challenging their use for model interpretation.

problem Current methods for model interpretability using input-gradients are flawed due to their arbitrary manipulability.
method Investigated by reinterpreting logits as unnormalized log-densities, proposing novel approximations for score-matching.
result Improving alignment between implicit density model and data distribution enhances gradient structure and explanatory power.

The Riemannian Langevin Algorithm samples from manifolds efficiently.

problem Sampling from distributions on manifolds with log-Sobolev inequality.
method Riemannian Langevin Algorithm, log-Sobolev inequality, self-concordance extension, stochastic smoothness bounding.
result The Riemannian Langevin Algorithm converges rapidly to the target density.