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Chang Yoo

13 accepted papers

2026

Decomposed On-Policy Distillation for Vision-Language Reasoning: Steering Gradients for Visual Grounding

ICML 2026spotlight

While on-policy distillation offers dense supervision for training small reasoning models, its optimization dynamics in the multimodal domain remain under-explored. In this work, we challenge the standard monolithic view of Vision-Language Model (VLM) distillation by mathematically decomposing the l…

Cited by 0SourceScholar
2026

Fast and Highly Expressive Policy Learning for Offline Reinforcement Learning via Bootstrapped Flow Q-Learning

ICML 2026poster

Diffusion-based Q-learning has emerged as a powerful paradigm for offline reinforcement learning, but its reliance on multi-step denoising makes both training and inference computationally expensive and brittle. Recent efforts to accelerate diffusion Q-learning toward single-step action generation t…

Cited by 0SourceScholar
2026

GADA: Geometry-Aware Deformable Aggregation for Image-Based Gaussian Splatting

ICML 2026poster

Gaussian Splatting has achieved significant improvements by incorporating warping-based techniques. These approaches enhance synthesis quality by warping images from source views into the target viewpoint to compensate for missing or residual pixels. However, such methods suffer from pixel-level ina…

Cited by 0SourceScholar
2026

Video-Based Optimal Transport for Feedback-Efficient Offline Preference-Based Reinforcement Learning

ICML 2026oral

Conveying complex objectives to reinforcement learning (RL) agents often requires meticulous reward engineering. Preference-based RL (PbRL) offers a promising alternative by learning reward functions from human feedback, but its scalability is hindered by high labeling costs. Inspired by advances in…

Cited by 0SourceScholar
2024

TLCR: Token-Level Continuous Reward for Fine-grained Reinforcement Learning from Human Feedback

ACL 2024findings

Reinforcement Learning from Human Feedback (RLHF) leverages human preference data to train language models to align more closely with human essence. These human preference data, however, are labeled at the sequence level, creating a mismatch between sequence-level preference labels and tokens, which…

2023

INTapt: Information-Theoretic Adversarial Prompt Tuning for Enhanced Non-Native Speech Recognition

ACL 2023findings

Automatic Speech Recognition (ASR) systems have attained unprecedented performance with large speech models pre-trained based on self-supervised speech representation learning. However, these pre-trained speech models suffer from representational bias as they tend to better represent those prominent…

Cited by 1SourcePDFScholar
2023

Listen, Decipher and Sign: Toward Unsupervised Speech-to-Sign Language Recognition

ACL 2023findings

Existing supervised sign language recognition systems rely on an abundance of well-annotated data. Instead, an unsupervised speech-to-sign language recognition (SSR-U) system learns to translate between spoken and sign languages by observing only non-parallel speech and sign-language corpora. We pro…

2022

Information-Theoretic Text Hallucination Reduction for Video-grounded Dialogue

EMNLP 2022main

Video-grounded Dialogue (VGD) aims to decode an answer sentence to a question regarding a given video and dialogue context. Despite the recent success of multi-modal reasoning to generate answer sentences, existing dialogue systems still suffer from a text hallucination problem, which denotes indisc…

2022

SMSMix: Sense-Maintained Sentence Mixup for Word Sense Disambiguation

EMNLP 2022finding

Word Sense Disambiguation (WSD) is an NLP task aimed at determining the correct sense of a word in a sentence from discrete sense choices. Although current systems have attained unprecedented performances for such tasks, the nonuniform distribution of word senses during training generally results in…

2022

Self-supervised Semantic-driven Phoneme Discovery for Zero-resource Speech Recognition

ACL 2022long

Phonemes are defined by their relationship to words: changing a phoneme changes the word. Learning a phoneme inventory with little supervision has been a longstanding challenge with important applications to under-resourced speech technology. In this paper, we bridge the gap between the linguistic a…

Cited by 4SourcePDFScholar
2021

Worldly Wise (WoW) - Cross-Lingual Knowledge Fusion for Fact-based Visual Spoken-Question Answering

NAACL 2021long

Although Question-Answering has long been of research interest, its accessibility to users through a speech interface and its support to multiple languages have not been addressed in prior studies. Towards these ends, we present a new task and a synthetically-generated dataset to do Fact-based Visua…

2019

Cascade RPN: Delving into High-Quality Region Proposal Network with Adaptive Convolution

NeurIPS 2019spotlight

This paper considers an architecture referred to as Cascade Region Proposal Network (Cascade RPN) for improving the region-proposal quality and detection performance by systematically addressing the limitation of the conventional RPN that heuristically defines the anchors and aligns the features to…