Mechanistic Indicators of Steering Effectiveness in Large Language Models
- URL: http://arxiv.org/abs/2602.01716v1
- Date: Mon, 02 Feb 2026 06:56:22 GMT
- Title: Mechanistic Indicators of Steering Effectiveness in Large Language Models
- Authors: Mehdi Jafari, Hao Xue, Flora Salim,
- Abstract summary: Activation-based steering enables Large Language Models to exhibit targeted behaviors by intervening on intermediate activations without retraining.<n>Despite its widespread use, the mechanistic factors that govern when steering succeeds or fails remain poorly understood.<n>We investigate whether the reliability of steering can be diagnosed using internal model signals.
- Score: 3.635648354808971
- License: http://creativecommons.org/licenses/by-nc-nd/4.0/
- Abstract: Activation-based steering enables Large Language Models (LLMs) to exhibit targeted behaviors by intervening on intermediate activations without retraining. Despite its widespread use, the mechanistic factors that govern when steering succeeds or fails remain poorly understood, as prior work has relied primarily on black-box outputs or LLM-based judges. In this study, we investigate whether the reliability of steering can be diagnosed using internal model signals. We focus on two information-theoretic measures: the entropy-derived Normalized Branching Factor (NBF), and the Kullback-Leibler (KL) divergence between steered activations and targeted concepts in the vocabulary space. We hypothesize that effective steering corresponds to structured entropy preservation and coherent KL alignment across decoding steps. Building on a reliability study demonstrating high inter-judge agreement between two architecturally distinct LLMs, we use LLM-generated annotations as ground truth and show that these mechanistic signals provide meaningful predictive power for identifying successful steering and estimating failure probability. We further introduce a stronger evaluation baseline for Contrastive Activation Addition (CAA) and Sparse Autoencoder-based steering, the two most widely adopted activation-steering methods.
Related papers
- ODESteer: A Unified ODE-Based Steering Framework for LLM Alignment [49.68063561145927]
We propose a unified ordinary differential equations (ODEs)-based theoretical framework for activation steering.<n>We introduce ODESteer, a kind of ODE-based steering guided by barrier functions.<n>Compared to state-of-the-art activation steering methods, ODESteer achieves consistent empirical improvements.
arXiv Detail & Related papers (2026-02-19T17:13:44Z) - From Passive Metric to Active Signal: The Evolving Role of Uncertainty Quantification in Large Language Models [77.04403907729738]
This survey charts the evolution of uncertainty from a passive diagnostic metric to an active control signal guiding real-time model behavior.<n>We demonstrate how uncertainty is leveraged as an active control signal across three frontiers.<n>This survey argues that mastering the new trend of uncertainty is essential for building the next generation of scalable, reliable, and trustworthy AI.
arXiv Detail & Related papers (2026-01-22T06:21:31Z) - Steering Language Models Before They Speak: Logit-Level Interventions [9.055997973281919]
We propose a training-free inference-time logit intervention for controllable generation.<n>Our results show that statistically grounded logit steering can achieve large, consistent, and multi-task control gains.
arXiv Detail & Related papers (2026-01-16T03:00:33Z) - RISER: Orchestrating Latent Reasoning Skills for Adaptive Activation Steering [62.63376387138257]
We propose a plug-and-play intervention framework that adaptively steers large language models (LLMs) reasoning in activation space.<n>RISER constructs a library of reusable reasoning vectors and employs a lightweight Router to dynamically compose them for each input.<n>The Router is optimized via reinforcement learning under task-level rewards, activating latent cognitive primitives in an emergent and compositional manner.
arXiv Detail & Related papers (2026-01-14T08:04:33Z) - Mechanistic Knobs in LLMs: Retrieving and Steering High-Order Semantic Features via Sparse Autoencoders [8.188989044347595]
We propose a Sparse Autoencoder-based framework for retrieving and steering semantically interpretable internal features.<n>Using the Big Five personality traits as a case study, we demonstrate that our method enables precise, bidirectional steering of model behavior.
arXiv Detail & Related papers (2026-01-06T12:40:37Z) - Activation Steering with a Feedback Controller [4.609594868699996]
Proportional-Integral-Derivative (PID) Steering is a principled framework that leverages the full PID controller for activation steering in large language models.<n>PID Steering consistently outperforms existing approaches, achieving more robust and reliable behavioral control.
arXiv Detail & Related papers (2025-10-05T18:05:28Z) - LatentGuard: Controllable Latent Steering for Robust Refusal of Attacks and Reliable Response Generation [4.29885665563186]
LATENTGUARD is a framework that combines behavioral alignment with supervised latent space control for interpretable and precise safety steering.<n>Our results show significant improvements in both safety controllability and response interpretability without compromising utility.
arXiv Detail & Related papers (2025-09-24T07:31:54Z) - KV Cache Steering for Controlling Frozen LLMs [80.50365534625438]
cache steering is a lightweight method for implicit steering of language models.<n>We apply cache steering to induce chain-of-thought reasoning in small language models.
arXiv Detail & Related papers (2025-07-11T17:59:36Z) - SafeAuto: Knowledge-Enhanced Safe Autonomous Driving with Multimodal Foundation Models [63.71984266104757]
We propose SafeAuto, a framework that enhances MLLM-based autonomous driving by incorporating both unstructured and structured knowledge.<n>To explicitly integrate safety knowledge, we develop a reasoning component that translates traffic rules into first-order logic.<n>Our Multimodal Retrieval-Augmented Generation model leverages video, control signals, and environmental attributes to learn from past driving experiences.
arXiv Detail & Related papers (2025-02-28T21:53:47Z) - InferAligner: Inference-Time Alignment for Harmlessness through
Cross-Model Guidance [56.184255657175335]
We develop textbfInferAligner, a novel inference-time alignment method that utilizes cross-model guidance for harmlessness alignment.
Experimental results show that our method can be very effectively applied to domain-specific models in finance, medicine, and mathematics.
It significantly diminishes the Attack Success Rate (ASR) of both harmful instructions and jailbreak attacks, while maintaining almost unchanged performance in downstream tasks.
arXiv Detail & Related papers (2024-01-20T10:41:03Z) - Steering Llama 2 via Contrastive Activation Addition [41.54815073311959]
Contrastive Activation Addition (CAA) is a method for steering language models by modifying their activations during forward passes.
CAA accurately steers model outputs and sheds light on how high-level concepts are represented in Large Language Models (LLMs)
arXiv Detail & Related papers (2023-12-09T04:40:46Z) - Empowering Autonomous Driving with Large Language Models: A Safety Perspective [82.90376711290808]
This paper explores the integration of Large Language Models (LLMs) into Autonomous Driving systems.
LLMs are intelligent decision-makers in behavioral planning, augmented with a safety verifier shield for contextual safety learning.
We present two key studies in a simulated environment: an adaptive LLM-conditioned Model Predictive Control (MPC) and an LLM-enabled interactive behavior planning scheme with a state machine.
arXiv Detail & Related papers (2023-11-28T03:13:09Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.