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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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163325488650 · Jun 202019922001200920172026
48 results for RKHS Functionals

Kernel methods are powerful tools to capture nonlinear patterns behind data. They implicitly learn high (even infinite) dimensional nonlinear features in the Reproducing Kernel Hilbert Space (RKHS) while making the computation tractable by leveraging the kernel trick. Classic kernel methods learn a single layer of nonl…

2017-11-25abs ↗pdf ↗

A new method for learning function parameters in operators using data-adaptive RKHS.

problem Learning function parameters in operators with robustness to noise and numerical error.
method Data Adaptive RKHS Tikhonov Regularization (DARTR) method.
result DARTR leads to an accurate estimator robust to noise and numerical error, converging at a consistent rate as data refines.

New analysis shows a gap between Gaussian RKHS and neural networks on unbounded domains.

problem Understanding the function space bias of neural networks compared to Gaussian RKHS.
method Infinite-center asymptotic analysis of neural network Banach space and Gaussian RKHS on unbounded domains.
result Certain functions in Gaussian RKHS have infinite norm in neural network Banach space on unbounded domains.

Paper explores RKHS properties for derivative and integral operators.

problem Establishing sufficient conditions for reproducing property in RKHS.
method Establishing reproducing property for combinations of composition operators.
result Provides framework for regularized learning algorithms involving function values, gradients, or operators.

This paper analyzes divide-and-conquer estimators for functional linear regression without assuming target function in the RKHS.

problem Functional linear regression without target function in RKHS.
method Integral operator approach to establish upper bounds and prove asymptotic optimality.
result Sharp finite sample upper bounds and asymptotic optimality of divide-and-conquer estimators.

This paper improves signal reconstruction using determinantal sampling from random nodes.

problem Approximating square-integrable functions from random node evaluations.
method Combines determinantal point processes and mixtures thereof for RKHS-adapted approximations.
result Proves mean-square guarantees in L2L^2 norm and shows faster convergence rates.

We study the approximation properties of random ReLU features through their reproducing kernel Hilbert space (RKHS). We first prove a universality theorem for the RKHS induced by random features whose feature maps are of the form of nodes in neural networks. The universality result implies that the random ReLU features…

2018-10-10abs ↗pdf ↗

Paper tackles tensor decomposition for unaligned observations using RKHS and novel loss functions.

problem Tackles tensor decomposition for unaligned observations.
method Uses functions in RKHS to represent mode with unaligned observations, introduces versatile loss function, proposes optimization algorithm and stochastic gradient method.
result Demonstrates improved tensor decomposition efficiency and effectiveness with synthetic and real data.

Kernel εε-Greedy optimizes multi-armed bandits with covariates for sub-linear regret.

problem Optimizing multi-armed bandits with covariates in a reproducing kernel Hilbert space.
method Online weighted kernel ridge regression estimator for mean reward function estimation.
result Achieves sub-linear regret rate and optimal T\sqrt{T} regret rate under margin condition.

A nonparametric kernel-based method for realizing Bayes' rule is proposed, based on representations of probabilities in reproducing kernel Hilbert spaces. Probabilities are uniquely characterized by the mean of the canonical map to the RKHS. The prior and conditional probabilities are expressed in terms of RKHS functio…

2010-09-29abs ↗pdf ↗

Study improves hypothesis transfer learning for functional linear models.

problem Incompatible TL techniques for high-dimensional FLR methods due to infinite-dimensional nature of functional data.
method Proposes two algorithms for hypothesis transfer learning in RKHS framework, leveraging RKHS distance and aggregation techniques.
result Establishes asymptotic lower bounds and matching upper bounds for the proposed algorithms, demonstrating their effectiveness.

Despite the fundamental nature of the inhomogeneous Poisson process in the theory and application of stochastic processes, and its attractive generalizations (e.g. Cox process), few tractable nonparametric modeling approaches of intensity functions exist, especially when observed points lie in a high-dimensional space.…

2016-10-27abs ↗pdf ↗

This paper generalizes regularized regression problems in a hyper-reproducing kernel Hilbert space (hyper-RKHS), illustrates its utility for kernel learning and out-of-sample extensions, and proves asymptotic convergence results for the introduced regression models in an approximation theory view. Algorithmically, we c…

2018-09-26abs ↗pdf ↗

This work analyzes the role of data augmentation in self-supervised learning using RKHS approximation and regression.

problem Limited theoretical understanding of the role of data augmentation in self-supervised learning.
method Geometric characterization of the target function given by augmentation, proving generalization bounds.
result Two generalization bounds are derived, one free of model complexity, the other specific to near-optimal encoders.

Improved GP bandit algorithms for noiseless, varying noise, and RKHS norms.

problem Minimizing regret in Gaussian process bandits with unknown reward functions.
method New upper bound on maximum posterior variance, refined MVR and PE algorithms.
result Optimal regret bounds for noiseless, varying noise, and RKHS norms.

We study quadrature rules for functions from an RKHS, using nodes sampled from a determinantal point process (DPP). DPPs are parametrized by a kernel, and we use a truncated and saturated version of the RKHS kernel. This link between the two kernels, along with DPP machinery, leads to relatively tight bounds on the qua…

2019-06-18abs ↗pdf ↗

We consider the problem of optimising functions in the reproducing kernel Hilbert space (RKHS) of a Matérn kernel with smoothness parameter νν over the domain [0,1]d[0,1]^d under noisy bandit feedback. Our contribution, the ππ-GP-UCB algorithm, is the first practical approach with guaranteed sublinear regret for all $ν>1…

2020-01-28abs ↗pdf ↗

Wide neural networks can outperform kernel methods in certain tasks.

problem Understanding when neural networks outperform kernel methods in classification tasks.
method Analyzing the performance of wide neural networks and kernel methods on various tasks, considering the initialization of SGD and the structure of covariates.
result Wide neural networks can outperform kernel methods in tasks where covariates have a low-dimensional structure similar to the target function.

Differential privacy is a framework for privately releasing summaries of a database. Previous work has focused mainly on methods for which the output is a finite dimensional vector, or an element of some discrete set. We develop methods for releasing functions while preserving differential privacy. Specifically, we sho…

2012-03-12abs ↗pdf ↗

Consider the problem: given the data pair (x,y)(\mathbf{x}, \mathbf{y}) drawn from a population with f(x)=E[yx=x]f_*(x) = \mathbf{E}[\mathbf{y} | \mathbf{x} = x], specify a neural network model and run gradient flow on the weights over time until reaching any stationarity. How does ftf_t, the function computed by the neural network…

2019-01-21abs ↗pdf ↗

Usually, complex-valued RKHS are presented as an straightforward application of the real-valued case. In this paper we prove that this procedure yields a limited solution for regression. We show that another kernel, here denoted as pseudo kernel, is needed to learn any function in complex-valued fields. Accordingly, we…

2016-10-31abs ↗pdf ↗

New particle-based VI algorithm expands function class and improves scalability.

problem Limited function class in particle-based VI algorithms restricts flexibility and scalability.
method Introduces a functional regularization term to expand the function class and proposes PFG algorithm.
result Proposed PFG algorithm has larger function class, improved scalability, better adaptation to ill-conditioned distributions, and provable convergence.

New method links covariates to CTMCs using RKHS, improving state transitions modeling.

problem Traditional multistate models rely on linear relationships, limiting flexibility.
method Nonparametric approach using RKHS, with Frequentist and Bayesian versions.
result Effective in identifying nonlinear transition functions and predicting long-term behaviors.

This study approximates distances between Gaussian processes and covariance operators using RKHS.

problem Approximating distances between Gaussian processes and covariance operators from finite samples.
method Using reproducing kernel Hilbert space (RKHS) covariance and cross-covariance operators, the study shows how to consistently and efficiently estimate Sinkhorn divergence from finite samples.
result Convergence rates are dimension-independent and of the same order as Hilbert-Schmidt distance.

We study distributed learning with the least squares regularization scheme in a reproducing kernel Hilbert space (RKHS). By a divide-and-conquer approach, the algorithm partitions a data set into disjoint data subsets, applies the least squares regularization scheme to each data subset to produce an output function, an…

2016-08-11abs ↗pdf ↗

New algorithm optimizes Hölder smooth functions in RKHS with tighter regret bounds.

problem Optimizing Hölder smooth functions in RKHS with bounded norm.
method Proposes a new algorithm ( exttt{LP-GP-UCB}) using Local Polynomial (LP) estimators and multi-scale UCB.
result Derives high probability bounds on simple and cumulative regret, matching optimal performance for SE kernel and uniformly tighter bounds for Matérn kernels.

We introduce a novel boosting algorithm called `KTBoost' which combines kernel boosting and tree boosting. In each boosting iteration, the algorithm adds either a regression tree or reproducing kernel Hilbert space (RKHS) regression function to the ensemble of base learners. Intuitively, the idea is that discontinuous …

2019-02-11abs ↗pdf ↗

Paper proposes a method to stabilize estimation of KL divergence using a discriminator in RKHS.

problem High variance and instability in estimating KL divergence using neural network discriminators.
method Developed a novel construction of the discriminator in RKHS, controlled its complexity, and proved the consistency of the estimator.
result Reduced variance and stabilized training of KL divergence estimates.

A new method for analyzing adaptive experiments using kernel treatment effects.

problem Efficiently analyzing adaptive experiments that adjust treatment assignments based on outcomes.
method Kernel Treatment Effects (KTE) framework combining RKHS scores and witness functions.
result Effective for both mean shifts and higher-moment differences, outperforming adaptive baselines.

The paper tackles data-driven optimal control of unknown nonlinear systems using RKHS.

problem Unknown nonlinear dynamics and stage cost functions.
method Embed state densities into RKHS, learn Markov operators, solve Hamilton-Jacobi-Bellman recursions.
result Solves a wide range of nonlinear control problems, including depth regulation.

Paper establishes lower bounds for non-stationary kernelized bandits.

problem Optimizing functions with noisy observations in non-stationary scenarios.
method Develops algorithm-independent lower bounds for time-varying functions under total variation constraints.
result First algorithm-independent lower bounds for time-varying kernelized bandits.

The paper identifies a 'small' set of functions containing Gaussian process samples.

problem Identifying a small set of functions containing Gaussian process samples.
method Using scaled RKHSs and Karhunen-Loève theorem, the paper defines the sample support set.
result The sample support set consists of functions with bounded squared basis coefficients.