← Search

Xianjun Yang

23 accepted papers

2026

Hallucination as a Computational Boundary: A Hierarchy of Inevitability and the Oracle Escape

AAAI 2026technical

The illusion phenomenon of large language models (LLMs) is the core obstacle to their reliable deployment. This article formalizes the large language model as a probabilistic Turing machine by constructing a "computational necessity hierarchy", and for the first time proves the illusions are inevita

Cited by 0SourcePDFScholar
2026

Verifying Chain-of-Thought Reasoning via Its Computational Graph

ICLR 2026oral

Current Chain-of-Thought (CoT) verification methods predict reasoning correctness based on outputs (black-box) or activations (gray-box), but offer limited insight into \textit{why} a computation fails. We introduce a white-box method: \textbf{Circuit-based Reasoning Verification (CRV)}. We hypothes…

Cited by 0SourcecodeScholar
2025

Beyond Training: Dynamic Token Merging for Zero-Shot Video Understanding

ICCV 2025poster

Recent advancements in multimodal large language models (MLLMs) have opened new avenues for video understanding. However, achieving high performance in zero-shot video tasks remains challenging. Traditional video processing methods rely heavily on fine-tuning to capture nuanced spatial-temporal deta…

2025

CBT-Bench: Evaluating Large Language Models on Assisting Cognitive Behavior Therapy

NAACL 2025long

There is a significant gap between patient needs and available mental health support today. In this paper, we aim to thoroughly examine the potential of using Large Language Models (LLMs) to assist professional psychotherapy. To this end, we propose a new benchmark, CBT-Bench, for the systematic eva…

Cited by 4SourcePDFScholar
2025

MELON: Provable Defense Against Indirect Prompt Injection Attacks in AI Agents

ICML 2025poster

Recent research has explored that LLM agents are vulnerable to indirect prompt injection (IPI) attacks, where malicious tasks embedded in tool-retrieved information can redirect the agent to take unauthorized actions. Existing defenses against IPI have significant limitations: either require essenti…

2025

Position Really Matters: Towards a Holistic Approach for Prompt Tuning

NAACL 2025findings

Prompt tuning is highly effective in efficiently extracting knowledge from foundation models, encompassing both language, vision, and vision-language models. However, the efficacy of employing fixed soft prompts with a predetermined position for concatenation with inputs for all instances, irrespect…

2025

Unveiling the Impact of Coding Data Instruction Fine-Tuning on Large Language Models Reasoning

AAAI 2025technical

Instruction Fine-Tuning (IFT) significantly enhances the zero-shot capabilities of pretrained Large Language Models (LLMs). While coding data is known to boost LLM reasoning abilities during pretraining, its role in activating internal reasoning capacities during IFT remains understudied. This paper…

2025

Weak-to-Strong Jailbreaking on Large Language Models

ICML 2025poster

Large language models (LLMs) are vulnerable to jailbreak attacks -- resulting in harmful, unethical, or biased text generations. However, existing jailbreaking methods are computationally costly. In this paper, we propose the **weak-to-strong** jailbreaking attack, an efficient inference time attack…

2024

A Self-Supervised Pressure Map Human Keypoint Detection Approch: Optimizing Generalization and Computational Efficiency Across Datasets

ICASSP 2024accepted

In environments where RGB images are inadequate, pressure maps is a viable alternative, garnering scholarly attention. This study introduces a novel self-supervised pressure map keypoint detection (SPMKD) method, addressing the current gap in specialized designs for human keypoint extraction from pr…

Cited by 0SourceScholar
2024

A Survey on Detection of LLMs-Generated Content

EMNLP 2024finding

The burgeoning capabilities of advanced large language models (LLMs) such as ChatGPT have led to an increase in synthetic content generation with implications across a variety of sectors, including media, cybersecurity, public discourse, and education. As such, the ability to detect LLMs-generated c…

2024

DALD: Improving Logits-based Detector without Logits from Black-box LLMs

NeurIPS 2024poster

The advent of Large Language Models (LLMs) has revolutionized text generation, producing outputs that closely mimic human writing. This blurring of lines between machine- and human-written text presents new challenges in distinguishing one from the other – a task further complicated by the frequent…

2024

DNA-GPT: Divergent N-Gram Analysis for Training-Free Detection of GPT-Generated Text

ICLR 2024poster

Large language models (LLMs) have notably enhanced the fluency and diversity of machine-generated text. However, this progress also presents a significant challenge in detecting the origin of a given text, and current research on detection methods lags behind the rapid evolution of LLMs. Conventiona…

2024

Enhancing Small Medical Learners with Privacy-preserving Contextual Prompting

ICLR 2024poster

Large language models (LLMs) demonstrate remarkable medical expertise, but data privacy concerns impede their direct use in healthcare environments. Although offering improved data privacy protection, domain-specific small language models (SLMs) often underperform LLMs, emphasizing the need for meth…

2024

Large Language Models Can Be Contextual Privacy Protection Learners

EMNLP 2024main

The proliferation of Large Language Models (LLMs) has driven considerable interest in fine-tuning them with domain-specific data to create specialized language models. Nevertheless, such domain-specific fine-tuning data often contains contextually sensitive personally identifiable information (PII).…

2024

MultiAgent Collaboration Attack: Investigating Adversarial Attacks in Large Language Model Collaborations via Debate

EMNLP 2024finding

Large Language Models (LLMs) have shown exceptional results on current benchmarks when working individually. The advancement in their capabilities, along with a reduction in parameter size and inference times, has facilitated the use of these models as agents, enabling interactions among multiple mo…

2024

Navigating the OverKill in Large Language Models

ACL 2024long

Large language models are meticulously aligned to be both helpful and harmless. However, recent research points to a potential overkill which means models may refuse to answer benign queries. In this paper, we investigate the factors for overkill by exploring how models handle and determine the safe…

Cited by 25SourcePDFScholar
2024

Position: A Safe Harbor for AI Evaluation and Red Teaming

ICML 2024oral

Independent evaluation and red teaming are critical for identifying the risks posed by generative AI systems. However, the terms of service and enforcement strategies used by prominent AI companies to deter model misuse have disincentives on good faith safety evaluations. This causes some researcher…

Cited by 5SourcePDFScholar
2024

TrustAgent: Towards Safe and Trustworthy LLM-based Agents

EMNLP 2024finding

The rise of LLM-based agents shows great potential to revolutionize task planning, capturing significant attention. Given that these agents will be integrated into high-stake domains, ensuring their reliability and safety is crucial. This paper presents an Agent-Constitution-based agent framework, T…

2023

LLMScore: Unveiling the Power of Large Language Models in Text-to-Image Synthesis Evaluation

NeurIPS 2023poster

Existing automatic evaluation on text-to-image synthesis can only provide an image-text matching score, without considering the object-level compositionality, which results in poor correlation with human judgments. In this work, we propose LLMScore, a new framework that offers evaluation scores with…

2023

OASum: Large-Scale Open Domain Aspect-based Summarization

ACL 2023findings

Aspect or query-based summarization has recently caught more attention, as it can generate differentiated summaries based on users’ interests. However, the current dataset for aspect or query-based summarization either focuses on specific domains, on a relatively small scale, or contains only a few…

2023

ReDi: Efficient Learning-Free Diffusion Inference via Trajectory Retrieval

ICML 2023poster

Diffusion models show promising generation capability for a variety of data. Despite their high generation quality, the inference for diffusion models is still time-consuming due to the numerous sampling iterations required. To accelerate the inference, we propose ReDi, a simple yet learning-free Re…

2022

PcMSP: A Dataset for Scientific Action Graphs Extraction from Polycrystalline Materials Synthesis Procedure Text

EMNLP 2022finding

Scientific action graphs extraction from materials synthesis procedures is important for reproducible research, machine automation, and material prediction. But the lack of annotated data has hindered progress in this field. We demonstrate an effort to annotate Polycrystalline Materials Synthesis Pr…