<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Yujun Kim | Junghyun Lee</title><link>https://nick-jhlee.github.io/collaborators/yujun-kim/</link><atom:link href="https://nick-jhlee.github.io/collaborators/yujun-kim/index.xml" rel="self" type="application/rss+xml"/><description>Yujun Kim</description><generator>Hugo Blox Builder (https://hugoblox.com)</generator><language>en-us</language><lastBuildDate>Thu, 21 May 2026 00:00:00 +0000</lastBuildDate><image><url>https://nick-jhlee.github.io/media/icon_hu_7613a4a452ac7087.png</url><title>Yujun Kim</title><link>https://nick-jhlee.github.io/collaborators/yujun-kim/</link></image><item><title>Looking Through the Mirror: Minimax-Optimal Regularized Regrets in Online Learning and Bandits</title><link>https://nick-jhlee.github.io/publication/arxiv26-regularized-regret/</link><pubDate>Thu, 21 May 2026 00:00:00 +0000</pubDate><guid>https://nick-jhlee.github.io/publication/arxiv26-regularized-regret/</guid><description>&lt;!--
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