🤖 AI Summary
This work addresses the challenge of hypothesis testing in high-dimensional regression when the underlying sparsity structure is unknown. The authors propose a unified L-statistic testing framework that adaptively aggregates the top-k strongest signals by ranking coordinate-wise evidence, thereby integrating both max-type and sum-type testing strategies. A key innovation is the Cauchy combination adaptive range test, which selects k via a dyadic grid search. The paper establishes theoretical guarantees by proving joint weak convergence and asymptotic independence between extreme-value components and normalized L-statistics. Combining extreme value theory, Cauchy combination methods, and wild bootstrap calibration, the proposed approach maintains accurate type I error control and high power under both sparse and dense alternatives, and remains valid for non-Gaussian design matrices.
📝 Abstract
We develop a unified $L$-statistic testing framework for high-dimensional regression coefficients that adapts to unknown sparsity. The proposed statistics rank coordinate-wise evidence measures and aggregate the top $k$ signals, bridging classical max-type and sum-type tests. We establish joint weak convergence of the extreme-value component and standardized $L$-statistics under mild conditions, yielding an asymptotic independence that justifies combining multiple $k$'s. An adaptive omnibus test is constructed via a Cauchy combination over a dyadic grid of $k$, and a wild bootstrap calibration is provided with theoretical guarantees. Simulations demonstrate accurate size and strong power across sparse and dense alternatives, including non-Gaussian designs.