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Yangyi Chen

25 accepted papers

2026

Perception-Aware Policy Optimization for Multimodal Reasoning

ICLR 2026poster

Reinforcement Learning with Verifiable Rewards (RLVR) has proven to be a highly effective strategy for empowering Large Language Models (LLMs) with long chain-of-thought reasoning abilities. However, its design and optimizations remain tailored to purely textual domains, resulting in suboptimal perf…

Cited by 0SourcecodeScholar
2025

SyncMind: Measuring Agent Out-of-Sync Recovery in Collaborative Software Engineering

ICML 2025poster

Software engineering (SE) is increasingly collaborative, with developers working together on shared complex codebases. Effective collaboration in shared environments requires participants---whether humans or AI agents---to stay on the same page as their environment evolves. When a collaborator's und…

2024

CRAFT: Customizing LLMs by Creating and Retrieving from Specialized Toolsets

ICLR 2024poster

Large language models (LLMs) are often augmented with tools to solve complex tasks. By generating code snippets and executing them through task-specific Application Programming Interfaces (APIs), they can offload certain functions to dedicated external modules, such as image encoding and performing…

2024

DRESS: Instructing Large Vision-Language Models to Align and Interact with Humans via Natural Language Feedback

CVPR 2024poster

We present DRESS a large vision language model (LVLM) that innovatively exploits Natural Language feedback (NLF) from Large Language Models to enhance its alignment and interactions by addressing two key limitations in the state-of-the-art LVLMs. First prior LVLMs generally rely only on the instruct…

Cited by 68SourcePDFScholar
2024

Executable Code Actions Elicit Better LLM Agents

ICML 2024poster

Large Language Model (LLM) agents, capable of performing a broad range of actions, such as invoking tools and controlling robots, show great potential in tackling real-world challenges. LLM agents are typically prompted to produce actions by generating JSON or text in a pre-defined format, which is…

Cited by 154SourcePDFScholar
2024

MINT: Evaluating LLMs in Multi-turn Interaction with Tools and Language Feedback

ICLR 2024poster

To solve complex tasks, large language models (LLMs) often require multiple rounds of interactions with the user, sometimes assisted by external tools. However, current evaluation protocols often emphasize benchmark performance with single-turn exchanges, neglecting the nuanced interactions among th…

Cited by 135SourcePDFScholar
2024

Measuring and Improving Chain-of-Thought Reasoning in Vision-Language Models

NAACL 2024long

Vision-language models (VLMs) have recently demonstrated strong efficacy as visual assistants that can parse natural queries about the visual content and generate human-like outputs. In this work, we explore the ability of these models to demonstrate human-like reasoning based on the perceived infor…

2024

R-Tuning: Instructing Large Language Models to Say ‘I Don’t Know’

NAACL 2024long

Large language models (LLMs) have revolutionized numerous domains with their impressive performance but still face their challenges. A predominant issue is the propensity for these models to generate non-existent facts, a concern termed hallucination. Our research is motivated by the observation tha…

2024

SaySelf: Teaching LLMs to Express Confidence with Self-Reflective Rationales

EMNLP 2024main

Large language models (LLMs) often generate inaccurate or fabricated information and generally fail to indicate their confidence, which limits their broader applications. Previous work has elicited confidence from LLMs by direct or self-consistency prompting, or constructing specific datasets for su…

2023

A Close Look into the Calibration of Pre-trained Language Models

ACL 2023long

Pre-trained language models (PLMs) may fail in giving reliable estimates of their predictive uncertainty. We take a close look into this problem, aiming to answer two questions: (1) Do PLMs learn to become calibrated in the training process? (2) How effective are existing calibration methods? For th…

2023

Beat LLMs at Their Own Game: Zero-Shot LLM-Generated Text Detection via Querying ChatGPT

EMNLP 2023short main

Large language models (LLMs), e.g., ChatGPT, have revolutionized the domain of natural language processing because of their excellent performance on various tasks. Despite their great potential, LLMs also incur serious concerns as they are likely to be misused. There are already reported cases of ac…

Cited by 0SourcecodeScholar
2023

Bridge the Gap Between CV and NLP! A Gradient-based Textual Adversarial Attack Framework

ACL 2023findings

Despite recent success on various tasks, deep learning techniques still perform poorly on adversarial examples with small perturbations. While optimization-based methods for adversarial attacks are well-explored in the field of computer vision, it is impractical to directly apply them in natural lan…

2023

From Adversarial Arms Race to Model-centric Evaluation: Motivating a Unified Automatic Robustness Evaluation Framework

ACL 2023findings

Textual adversarial attacks can discover models’ weaknesses by adding semantic-preserved but misleading perturbations to the inputs. The long-lasting adversarial attack-and-defense arms race in Natural Language Processing (NLP) is algorithm-centric, providing valuable techniques for automatic robust…

2023

Making Pre-trained Language Models both Task-solvers and Self-calibrators

ACL 2023findings

Pre-trained language models (PLMs) serve as backbones for various real-world systems. For high-stake applications, it’s equally essential to have reasonable confidence estimations in predictions. While the vanilla confidence scores of PLMs can already be effectively utilized, PLMs consistently becom…

2023

Revisiting Out-of-distribution Robustness in NLP: Benchmarks, Analysis, and LLMs Evaluations

NeurIPS 2023poster

This paper reexamines the research on out-of-distribution (OOD) robustness in the field of NLP. We find that the distribution shift settings in previous studies commonly lack adequate challenges, hindering the accurate evaluation of OOD robustness. To address these issues, we propose a benchmark con…

2023

ViStruct: Visual Structural Knowledge Extraction via Curriculum Guided Code-Vision Representation

EMNLP 2023long main

State-of-the-art vision-language models (VLMs) still have limited performance in structural knowledge extraction, such as relations between objects. In this work, we present ViStruct, a training framework to learn VLMs for effective visual structural knowledge extraction. Two novel designs are incor…

Cited by 0SourcecodeScholar
2022

A Unified Evaluation of Textual Backdoor Learning: Frameworks and Benchmarks

NeurIPS 2022accept

Textual backdoor attacks are a kind of practical threat to NLP systems. By injecting a backdoor in the training phase, the adversary could control model predictions via predefined triggers. As various attack and defense models have been proposed, it is of great significance to perform rigorous evalu…

2022

Exploring the Universal Vulnerability of Prompt-based Learning Paradigm

NAACL 2022findings

Prompt-based learning paradigm bridges the gap between pre-training and fine-tuning, and works effectively under the few-shot setting. However, we find that this learning paradigm inherits the vulnerability from the pre-training stage, where model predictions can be misled by inserting certain trigg…

2022

Moderate-fitting as a Natural Backdoor Defender for Pre-trained Language Models

NeurIPS 2022accept

Despite the great success of pre-trained language models (PLMs) in a large set of natural language processing (NLP) tasks, there has been a growing concern about their security in real-world applications. Backdoor attack, which poisons a small number of training samples by inserting backdoor trigger…

2022

Textual Backdoor Attacks Can Be More Harmful via Two Simple Tricks

EMNLP 2022main

Backdoor attacks are a kind of emergent security threat in deep learning. After being injected with a backdoor, a deep neural model will behave normally on standard inputs but give adversary-specified predictions once the input contains specific backdoor triggers. In this paper, we find two simple t…

2022

Why Should Adversarial Perturbations be Imperceptible? Rethink the Research Paradigm in Adversarial NLP

EMNLP 2022main

Textual adversarial samples play important roles in multiple subfields of NLP research, including security, evaluation, explainability, and data augmentation. However, most work mixes all these roles, obscuring the problem definitions and research goals of the security role that aims to reveal the p…

2021

Hidden Killer: Invisible Textual Backdoor Attacks with Syntactic Trigger

ACL 2021long

Backdoor attacks are a kind of insidious security threat against machine learning models. After being injected with a backdoor in training, the victim model will produce adversary-specified outputs on the inputs embedded with predesigned triggers but behave properly on normal inputs during inference…

2021

Mind the Style of Text! Adversarial and Backdoor Attacks Based on Text Style Transfer

EMNLP 2021main

Adversarial attacks and backdoor attacks are two common security threats that hang over deep learning. Both of them harness task-irrelevant features of data in their implementation. Text style is a feature that is naturally irrelevant to most NLP tasks, and thus suitable for adversarial and backdoor…

2021

ONION: A Simple and Effective Defense Against Textual Backdoor Attacks

EMNLP 2021main

Backdoor attacks are a kind of emergent training-time threat to deep neural networks (DNNs). They can manipulate the output of DNNs and possess high insidiousness. In the field of natural language processing, some attack methods have been proposed and achieve very high attack success rates on multip…