Efficient Aggregated Kernel Tests using Incomplete $U$-statistics
- URL: http://arxiv.org/abs/2206.09194v1
- Date: Sat, 18 Jun 2022 12:30:06 GMT
- Title: Efficient Aggregated Kernel Tests using Incomplete $U$-statistics
- Authors: Antonin Schrab and Ilmun Kim and Benjamin Guedj and Arthur Gretton
- Abstract summary: Three proposed tests aggregate over several kernel bandwidths to detect departures from the null on various scales.
We show that our proposed linear-time aggregated tests obtain higher power than current state-of-the-art linear-time kernel tests.
- Score: 22.251118308736327
- License: http://creativecommons.org/licenses/by-nc-sa/4.0/
- Abstract: We propose a series of computationally efficient, nonparametric tests for the
two-sample, independence and goodness-of-fit problems, using the Maximum Mean
Discrepancy (MMD), Hilbert Schmidt Independence Criterion (HSIC), and Kernel
Stein Discrepancy (KSD), respectively. Our test statistics are incomplete
$U$-statistics, with a computational cost that interpolates between linear time
in the number of samples, and quadratic time, as associated with classical
$U$-statistic tests. The three proposed tests aggregate over several kernel
bandwidths to detect departures from the null on various scales: we call the
resulting tests MMDAggInc, HSICAggInc and KSDAggInc. For the test thresholds,
we derive a quantile bound for wild bootstrapped incomplete $U$- statistics,
which is of independent interest. We derive uniform separation rates for
MMDAggInc and HSICAggInc, and quantify exactly the trade-off between
computational efficiency and the attainable rates: this result is novel for
tests based on incomplete $U$-statistics, to our knowledge. We further show
that in the quadratic-time case, the wild bootstrap incurs no penalty to test
power over more widespread permutation-based approaches, since both attain the
same minimax optimal rates (which in turn match the rates that use oracle
quantiles). We support our claims with numerical experiments on the trade-off
between computational efficiency and test power. In the three testing
frameworks, we observe that our proposed linear-time aggregated tests obtain
higher power than current state-of-the-art linear-time kernel tests.
Related papers
- Doubly Robust Conditional Independence Testing with Generative Neural Networks [8.323172773256449]
This article addresses the problem of testing the conditional independence of two generic random vectors $X$ and $Y$ given a third random vector $Z$.
We propose a new non-parametric testing procedure that avoids explicitly estimating any conditional distributions.
arXiv Detail & Related papers (2024-07-25T01:28:59Z) - Collaborative non-parametric two-sample testing [55.98760097296213]
The goal is to identify nodes where the null hypothesis $p_v = q_v$ should be rejected.
We propose the non-parametric collaborative two-sample testing (CTST) framework that efficiently leverages the graph structure.
Our methodology integrates elements from f-divergence estimation, Kernel Methods, and Multitask Learning.
arXiv Detail & Related papers (2024-02-08T14:43:56Z) - Precise Error Rates for Computationally Efficient Testing [75.63895690909241]
We revisit the question of simple-versus-simple hypothesis testing with an eye towards computational complexity.
An existing test based on linear spectral statistics achieves the best possible tradeoff curve between type I and type II error rates.
arXiv Detail & Related papers (2023-11-01T04:41:16Z) - A Specialized Semismooth Newton Method for Kernel-Based Optimal
Transport [92.96250725599958]
Kernel-based optimal transport (OT) estimators offer an alternative, functional estimation procedure to address OT problems from samples.
We show that our SSN method achieves a global convergence rate of $O (1/sqrtk)$, and a local quadratic convergence rate under standard regularity conditions.
arXiv Detail & Related papers (2023-10-21T18:48:45Z) - Boosting the Power of Kernel Two-Sample Tests [4.07125466598411]
A kernel two-sample test based on the maximum mean discrepancy (MMD) is one of the most popular methods for detecting differences between two distributions over general metric spaces.
We propose a method to boost the power of the kernel test by combining MMD estimates over multiple kernels using their Mahalanobis distance.
arXiv Detail & Related papers (2023-02-21T14:14:30Z) - Compress Then Test: Powerful Kernel Testing in Near-linear Time [27.723775378945643]
Kernel two-sample testing provides a powerful framework for distinguishing any pair of distributions based on $n$ sample points.
We introduce Compress Then Test (CTT), a new framework for high-powered kernel testing based on sample compression.
CTT cheaply approximates an expensive test by compressing each $n$ point sample into a small but provably high-fidelity coreset.
arXiv Detail & Related papers (2023-01-14T21:02:58Z) - Sequential Kernelized Independence Testing [101.22966794822084]
We design sequential kernelized independence tests inspired by kernelized dependence measures.
We demonstrate the power of our approaches on both simulated and real data.
arXiv Detail & Related papers (2022-12-14T18:08:42Z) - A Permutation-free Kernel Two-Sample Test [36.50719125230106]
We propose a new quadratic-time MMD test statistic based on sample-splitting and studentization.
For large sample sizes, our new cross-MMD provides a significant speedup over the MMD, for only a slight loss in power.
arXiv Detail & Related papers (2022-11-27T18:15:52Z) - Nonparametric Conditional Local Independence Testing [69.31200003384122]
Conditional local independence is an independence relation among continuous time processes.
No nonparametric test of conditional local independence has been available.
We propose such a nonparametric test based on double machine learning.
arXiv Detail & Related papers (2022-03-25T10:31:02Z) - KSD Aggregated Goodness-of-fit Test [38.45086141837479]
We introduce a strategy to construct a test, called KSDAgg, which aggregates multiple tests with different kernels.
We provide non-asymptotic guarantees on the power of KSDAgg.
We find that KSDAgg outperforms other state-of-the-art adaptive KSD-based goodness-of-fit testing procedures.
arXiv Detail & Related papers (2022-02-02T00:33:09Z) - Computationally efficient sparse clustering [67.95910835079825]
We provide a finite sample analysis of a new clustering algorithm based on PCA.
We show that it achieves the minimax optimal misclustering rate in the regime $|theta infty$.
arXiv Detail & Related papers (2020-05-21T17:51:30Z)
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.