New Bounds for Kernel Sums via Fast Spherical Embeddings
- URL: http://arxiv.org/abs/2605.01263v1
- Date: Sat, 02 May 2026 05:42:50 GMT
- Title: New Bounds for Kernel Sums via Fast Spherical Embeddings
- Abstract summary: We prove a new bound $tilde O(d+varepsilon2+1/varepsilon3)$, which improves over the previous ones in regimes with small error.<n>At the center of our proof is a new fast spherical embedding theorem in the sense introduced by Bartal, Recht and Schulman (2011), which limits the embedded data diameter.
- Score: 12.14121214083427
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We study query time bounds for the fundamental problem of estimating the kernel mean $\frac1{|X|}\sum_{x\in X}\mathbf{k}(x,y)$ of a query $y$ in a finite dataset $X\subset\mathbb{R}^d$ up to a prescribed additive error $\varepsilon$. The best known bounds for the Gaussian kernel are $O(d/\varepsilon^2)$, $\widetilde O(d+1/\varepsilon^4)$, and $\widetilde O(d+Δ^2/\varepsilon^2)$, where $Δ$ is the diameter of a region containing the points. We prove the new bound $\tilde O(d+\varepsilonΔ^2+1/\varepsilon^3)$, which improves over the previous ones in regimes with small error $\varepsilon$ and intermediate diameter $Δ$. At the center of our proof is a new fast spherical embedding theorem in the sense introduced by Bartal, Recht and Schulman (2011), which limits the embedded data diameter while preserving local Euclidean distances and avoiding ``distance collapse'' at larger scales. This fast embedding theorem may be of independent interest.
Related papers
- Low-Dimensional Embeddings for Gaussian Kernels on Manifolds [0.42970700836450487]
We show that for points in a $d$-dimensional Euclidean ball in $mathbb RN$, $t=((d/varepsilon2)log(dR/varepsilon))$ features suffice to preserve all pairwise Gaussian kernel distances.<n>We also prove a topological consequence: under the same RFF embedding, persistent homology is preserved in the sense that weighted Cech and Rips filtrations built from Gaussian kernel power distance are $(pmvarepsilon_star)$-interleaved.
arXiv Detail & Related papers (2026-09-14T08:00:56Z) - The Condition-Number Barrier in Sparse Least Squares [77.64108812086542]
In [AS21], Axiotis and Sviridenko conjectured that the linear dependence on the restricted condition number in convex optimization cannot be improved by a sparse-time algorithm.<n>We establish their conjectured lower bound for least-squares objectives, conditional on the randomized exact-volume Small-Set Expansion Hypothesis.
arXiv Detail & Related papers (2026-08-03T17:57:01Z) - Near-Optimal Convergence of Accelerated Gradient Methods under Generalized and $(L_0, L_1)$-Smoothness [57.93371273485736]
We study first-order methods for convex optimization problems with functions $f$ satisfying the recently proposed $ell$-smoothness condition $||nabla2f(x)|| le ellleft(||nabla f(x)||right),$ which generalizes the $L$-smoothness and $(L_0,L_1)$-smoothness.
arXiv Detail & Related papers (2025-08-09T08:28:06Z) - Almost Minimax Optimal Best Arm Identification in Piecewise Stationary Linear Bandits [55.957560311008926]
We propose a piecewise stationary linear bandit (PSLB) model where the quality of an arm is measured by its return averaged over all contexts.
PS$varepsilon$BAI$+$ is guaranteed to identify an $varepsilon$-optimal arm with probability $ge 1-delta$ and with a minimal number of samples.
arXiv Detail & Related papers (2024-10-10T06:15:42Z) - Dimension-Independent Kernel ε-Covers [8.234735564035567]
A kernel range space concerns a set of points $X subset mathbbRd$ and the space of all queries by a fixed kernel.<n>We introduce the notion of an $varepsilon$-cover for a kernel range space.
arXiv Detail & Related papers (2023-06-28T19:19:33Z) - Fast $(1+\varepsilon)$-Approximation Algorithms for Binary Matrix
Factorization [54.29685789885059]
We introduce efficient $(1+varepsilon)$-approximation algorithms for the binary matrix factorization (BMF) problem.
The goal is to approximate $mathbfA$ as a product of low-rank factors.
Our techniques generalize to other common variants of the BMF problem.
arXiv Detail & Related papers (2023-06-02T18:55:27Z) - Improved Coresets for Euclidean $k$-Means [24.850829728643923]
Given a set of $n$ points in $d$ dimensions, the Euclidean $k$-means problem (resp. the Euclidean $k$-median problem) consists of finding $k$ centers.
In this paper, we improve the upper bounds $tilde O(min(k2 cdot varepsilon-2,kcdot varepsilon-4)$ for $k$-means and $tilde O(min(k4/3 cdot varepsilon
arXiv Detail & Related papers (2022-11-15T14:47:24Z) - Non-asymptotic spectral bounds on the $\varepsilon$-entropy of kernel classes [4.178980693837599]
This topic is an important direction in the modern statistical theory of kernel-based methods.<n>We discuss a number of consequences of our bounds and show that they are substantially tighter than bounds for general kernels.
arXiv Detail & Related papers (2022-04-09T16:45:22Z) - Low-degree learning and the metric entropy of polynomials [44.99833362998488]
We prove that any (deterministic or randomized) algorithm which learns $mathscrF_nd$ with $L$-accuracy $varepsilon$ requires at least $Omega(sqrtvarepsilon)2dlog n leq log mathsfM(mathscrF_n,d,|cdot|_L,varepsilon) satisfies the two-sided estimate $$c (1-varepsilon)2dlog
arXiv Detail & Related papers (2022-03-17T23:52:08Z) - Learning low-degree functions from a logarithmic number of random
queries [77.34726150561087]
We prove that for any integer $ninmathbbN$, $din1,ldots,n$ and any $varepsilon,deltain(0,1)$, a bounded function $f:-1,1nto[-1,1]$ of degree at most $d$ can be learned.
arXiv Detail & Related papers (2021-09-21T13:19:04Z) - Threshold Phenomena in Learning Halfspaces with Massart Noise [56.01192577666607]
We study the problem of PAC learning halfspaces on $mathbbRd$ with Massart noise under Gaussian marginals.
Our results qualitatively characterize the complexity of learning halfspaces in the Massart model.
arXiv Detail & Related papers (2021-08-19T16:16:48Z) - Approximate Maximum Halfspace Discrepancy [6.35821487778241]
We consider the range space $(X, mathcalH_d)$ where $X subset mathbbRd$ and $mathcalH_d$ is the set of ranges defined by $d$ halfspaces.
For each halfspace $h in mathcalH_d$ define a function $Phi(h)$ that measures the "difference" between the fraction of red and fraction of blue points which fall in the range $h$.
arXiv Detail & Related papers (2021-06-25T19:14:45Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.