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Xintong Li

20 accepted papers

2026

Importance Sampling for Multi-Negative Multimodal Direct Preference Optimization

ICLR 2026poster

Direct Preference Optimization (DPO) has recently been extended from text-only models to vision-language models. However, existing methods rely on oversimplified pairwise comparisons, generating a single negative image via basic perturbations or similarity-based retrieval, which fail to capture the…

Cited by 0SourceScholar
2026

WS-GRPO: Weakly-Supervised Group-Relative Policy Optimization for Rollout-Efficient Reasoning

ICML 2026poster

Group Relative Policy Optimization (GRPO) is effective for training language models on complex reasoning. However, since the objective is defined relative to a group of sampled trajectories, extended deliberation can create more chances to realize relative gains, leading to inefficient reasoning and…

Cited by 0SourceScholar
2025

Explainable Chain-of-Thought Reasoning: An Empirical Analysis on State-Aware Reasoning Dynamics

EMNLP 2025

Recent advances in chain-of-thought (CoT) prompting have demonstrated the ability of large language models (LLMs) to perform multi-step reasoning. While prior work focuses on improving CoT generation quality or attributing token-level importance, we propose a novel framework to structurally analyze

Cited by 0SourcePDFScholar
2025

FAP-CD: Fairness-Driven Age-Friendly Community Planning via Conditional Diffusion Generation

AAAI 2025technical

As global populations age rapidly, incorporating age-specific considerations into urban planning has become essential to addressing the urgent demand for age-friendly built environments and ensuring sustainable urban development. However, current practices often overlook these considerations, result…

2025

From Selection to Generation: A Survey of LLM-based Active Learning

ACL 2025long

Active Learning (AL) has been a powerful paradigm for improving model efficiency and performance by selecting the most informative data points for labeling and training. In recent active learning frameworks, Large Language Models (LLMs) have been employed not only for selection but also for generati…

Cited by 0SourcePDFScholar
2025

Mitigating Visual Knowledge Forgetting in MLLM Instruction-tuning via Modality-decoupled Gradient Descent

EMNLP 2025

Recent MLLMs have demonstrated strong visual understanding and reasoning after large-scale multimodal pre-training. However, instruction-tuning is typically text-driven with limited visual supervision, leading to significant visual forgetting and degradation of pre-trained visual knowledge. Existing

Cited by 12SourcePDFScholar
2025

OCEAN: Offline Chain-of-thought Evaluation and Alignment in Large Language Models

ICLR 2025poster

Offline evaluation of LLMs is crucial in understanding their capacities, though current methods remain underexplored in existing research. In this work, we focus on the offline evaluation of the chain-of-thought capabilities and show how to optimize LLMs based on the proposed evaluation method. To e…

Cited by 0SourcePDFScholar
2025

Toward Multi-Session Personalized Conversation: A Large-Scale Dataset and Hierarchical Tree Framework for Implicit Reasoning

EMNLP 2025

There has been a surge in the use of large language models (LLM) conversational agents to generate responses based on long-term history from multiple sessions. However, existing long-term open-domain dialogue datasets lack complex, real-world personalization and fail to capture implicit reasoning—wh

2024

Cocktail Universal Adversarial Attack on Deep Neural Networks

ECCV 2024poster

"Deep neural networks (DNNs) for image classification are known to be susceptible to many diversified universal adversarial perturbations (UAPs), where each UAP successfully attacks a large but substantially different set of images. Properly combining the diversified UAPs can significantly improve t…

Cited by 0SourcePDFScholar
2024

Open-world Multi-label Text Classification with Extremely Weak Supervision

EMNLP 2024main

We study open-world multi-label text classification under extremely weak supervision (XWS), where the user only provides a brief description for classification objectives without any labels or ground-truth label space. Similar single-label XWS settings have been explored recently, however, these met…

2023

Geometry-Aware Adaptation for Pretrained Models

NeurIPS 2023poster

Machine learning models---including prominent zero-shot models---are often trained on datasets whose labels are only a small proportion of a larger label space. Such spaces are commonly equipped with a metric that relates the labels via distances between them. We propose a simple approach to exploit…

Cited by 4SourcePDFScholar
2022

A$^3$T: Alignment-Aware Acoustic and Text Pretraining for Speech Synthesis and Editing

ICML 2022spotlight

Recently, speech representation learning has improved many speech-related tasks such as speech recognition, speech classification, and speech-to-text translation. However, all the above tasks are in the direction of speech understanding, but for the inverse direction, speech synthesis, the potential…

2022

AutoWS-Bench-101: Benchmarking Automated Weak Supervision with 100 Labels

NeurIPS 2022accept

Weak supervision (WS) is a powerful method to build labeled datasets for training supervised models in the face of little-to-no labeled data. It replaces hand-labeling data with aggregating multiple noisy-but-cheap label estimates expressed by labeling functions (LFs). While it has been used success…

Cited by 8SourcePDFScholar
2022

PaddleSpeech: An Easy-to-Use All-in-One Speech Toolkit

NAACL 2022system demonstrations

PaddleSpeech is an open-source all-in-one speech toolkit. It aims at facilitating the development and research of speech processing technologies by providing an easy-to-use command-line interface and a simple code structure. This paper describes the design philosophy and core architecture of PaddleS…

2021

Building Adaptive Acceptability Classifiers for Neural NLG

EMNLP 2021main

We propose a novel framework to train models to classify acceptability of responses generated by natural language generation (NLG) models, improving upon existing sentence transformation and model-based approaches. An NLG response is considered acceptable if it is both semantically correct and gramm…

2018

Efficient Object Search With Belief Road Map Using Mobile Robot

RA-L 2018

This letter describes a pipeline for autonomous object search using a mobile robot. The robot is required to efficiently find an object in an unknown environment. In this letter, we formulate the object-search problem as a Partially Observable Markov Decision Process (POMDP). The semantic informatio

Cited by 44SourceScholar