CorrSteer: Steering Improves Task Performance and Safety in LLMs through
  Correlation-based Sparse Autoencoder Feature Selection
Authors: name: Seonglae Cho; name: Zekun Wu; name: Adriano Koshiyama
Published: 2025-08-18 00:01:42

Abstract: Sparse Autoencoders (SAEs) can extract interpretable features from large
language models (LLMs) without supervision. However, their effectiveness in
downstream steering tasks is limited by the requirement for contrastive
datasets or large activation storage. To address these limitations, we propose
CorrSteer, which selects features by correlating sample correctness with SAE
activations from generated tokens at inference time. This approach uses only
inference-time activations to extract more relevant features, thereby avoiding
spurious correlations. It also obtains steering coefficients from average
activations, automating the entire pipeline. Our method shows improved task
performance on QA, bias mitigation, jailbreaking prevention, and reasoning
benchmarks on Gemma 2 2B and LLaMA 3.1 8B, notably achieving a +4.1%
improvement in MMLU performance and a +22.9% improvement in HarmBench with only
4000 samples. Selected features demonstrate semantically meaningful patterns
aligned with each task's requirements, revealing the underlying capabilities
that drive performance. Our work establishes correlationbased selection as an
effective and scalable approach for automated SAE steering across language
model applications.