<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Theory | Jingshu Wang</title><link>https://jingshuw.org/tag/theory/</link><atom:link href="https://jingshuw.org/tag/theory/index.xml" rel="self" type="application/rss+xml"/><description>Theory</description><generator>Wowchemy (https://wowchemy.com)</generator><language>en-us</language><copyright>'@copy;' Jingshu Wang 2026</copyright><lastBuildDate>Thu, 07 Aug 2025 00:00:00 +0000</lastBuildDate><image><url>https://jingshuw.org/images/icon_hua2ec155b4296a9c9791d015323e16eb5_11927_512x512_fill_lanczos_center_2.png</url><title>Theory</title><link>https://jingshuw.org/tag/theory/</link></image><item><title>Preprint: Validity and Power of Heavy-Tailed Combination Tests under Asymptotic Dependence</title><link>https://jingshuw.org/post/heavytail-combination-2025/</link><pubDate>Thu, 07 Aug 2025 00:00:00 +0000</pubDate><guid>https://jingshuw.org/post/heavytail-combination-2025/</guid><description>&lt;p>We have posted a new preprint on Arxiv, &lt;em>Validity and Power of Heavy-Tailed Combination Tests under Asymptotic Dependence&lt;/em>, develops a unified theoretical framework for understanding the behavior of heavy-tailed p-value combination methods under broad dependence structures:&lt;/p>
&lt;p>👉 &lt;a href="https://arxiv.org/abs/2508.05818" target="_blank" rel="noopener">arXiv:2508.05818&lt;/a>&lt;/p>
&lt;p>Using multivariate regularly varying copulas to characterize joint lower-tail behavior, the paper shows:&lt;/p>
&lt;ul>
&lt;li>Heavy-tailed combination tests remain asymptotically valid when p-values have multivariate regularly varying copulas the transformation distribution has tail index ( \gamma \le 1 ).&lt;/li>
&lt;li>The choice ( \gamma = 1 ) maximizes power while preserving validity.&lt;/li>
&lt;li>Bonferroni emerges as the limiting ( \gamma \to 0 ) case and becomes overly conservative under asymptotic dependence.&lt;/li>
&lt;li>Heavy-tailed tests with ( \gamma = 1 ) (e.g., truncated Cauchy or Pareto combinations) achieve increasing asymptotic power gains as lower-tail dependence strengthens.&lt;/li>
&lt;/ul>
&lt;p>The framework provides theoretical support for using heavy-tailed combination tests to enhance power while controlling false positives under complex dependence.&lt;/p></description></item></channel></rss>