Saved in:
Bibliographic Details
Main Authors: Si, Wai Man, Li, Mingjie, Backes, Michael, Zhang, Yang
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2604.15789
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915941948850176
author Si, Wai Man
Li, Mingjie
Backes, Michael
Zhang, Yang
author_facet Si, Wai Man
Li, Mingjie
Backes, Michael
Zhang, Yang
contents As Large Language Models (LLMs) receive increasing attention and are being deployed across various domains, their potential risks, including generating harmful or biased content, producing unsupported claims, and exhibiting vulnerabilities to adversarial attacks, have drawn significant attention. To enable quick and low-cost adaptation, training-free methods have recently emerged as cost-effective alternatives to post-training alignment techniques. Despite their promising results, these methods are evaluated inconsistently across the literature, cover limited dimensions of trustworthiness, and can introduce undesirable side effects, such as utility degradation and increased brittleness. To fully assess the impacts of these training-free methods, we take a step back and systematically re-evaluate the effectiveness of existing training-free methods against various trustworthy settings and their influence on utility, robustness, and computational overhead. We also categorize these methods into three levels (input, internal, and output) based on where they intervene in the model's information flow during inference. Using this taxonomy, we conduct a comprehensive analysis of various representative and effective methods from each level across different LLM families and sizes. Our analysis highlights several trade-offs and unresolved challenges in current approaches. We summarize key findings and limitations in the existing literature, and propose practical recommendations for balancing trustworthiness, utility, and robustness in LLMs without the need for additional training.
format Preprint
id arxiv_https___arxiv_org_abs_2604_15789
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A Systematic Study of Training-Free Methods for Trustworthy Large Language Models
Si, Wai Man
Li, Mingjie
Backes, Michael
Zhang, Yang
Computation and Language
As Large Language Models (LLMs) receive increasing attention and are being deployed across various domains, their potential risks, including generating harmful or biased content, producing unsupported claims, and exhibiting vulnerabilities to adversarial attacks, have drawn significant attention. To enable quick and low-cost adaptation, training-free methods have recently emerged as cost-effective alternatives to post-training alignment techniques. Despite their promising results, these methods are evaluated inconsistently across the literature, cover limited dimensions of trustworthiness, and can introduce undesirable side effects, such as utility degradation and increased brittleness. To fully assess the impacts of these training-free methods, we take a step back and systematically re-evaluate the effectiveness of existing training-free methods against various trustworthy settings and their influence on utility, robustness, and computational overhead. We also categorize these methods into three levels (input, internal, and output) based on where they intervene in the model's information flow during inference. Using this taxonomy, we conduct a comprehensive analysis of various representative and effective methods from each level across different LLM families and sizes. Our analysis highlights several trade-offs and unresolved challenges in current approaches. We summarize key findings and limitations in the existing literature, and propose practical recommendations for balancing trustworthiness, utility, and robustness in LLMs without the need for additional training.
title A Systematic Study of Training-Free Methods for Trustworthy Large Language Models
topic Computation and Language
url https://arxiv.org/abs/2604.15789