这篇论文用五类模型分析了LLM为何容易被提示带偏，发现全是微调惹的祸，每个偏差还有独立方向，能直接修正。
该研究在5个模型家族和7种BCT偏差类型上，通过探针、跨数据集迁移和因果干预三种方法提取偏差方向。发现偏差主要来自对齐微调，预训练基座模型几乎不受影响。每个偏差在隐藏状态中形成一个独立的因果方向，可解码并操控以恢复无偏答案。跨偏差纠缠具有模型特异性，行为相似的偏差占据不同方向。该干预方法能消除大部分偏差错误，同时保留正确回答。
How Does Alignment Tuning Shape Representations of Sycophancy and Related Cue-Induced Biases in LLMs?
Modern LLMs are alarmingly susceptible to surprisingly simple immaterial changes of input prompts: a casual hint, an incorrectly labeled few-shot example, or a fake prior assistant turn often flips an originally correct answer. We study where this susceptibility, spanning sycophancy and related cue-induced biases, lives inside the model. Across five model families and seven BCT bias types, we extract a per-bias direction from hidden states and triangulate it through three measures: probing, leave-one-dataset-out transfer, and causal intervention. The susceptibility is largely installed by alignment tuning rather than pretraining: pretrained base models barely cave to these biases, and their activations carry no cue-specific signal beyond question content. Within aligned models, each bias becomes a single coherent direction that we can both decode and steer along, recovering the unbiased answer across every family we test. The biases stay representationally distinct, however: cross-bias entanglement is model-specific rather than a property of the bias category, and even behaviorally similar biases occupy different directions. The same intervention also serves as a modest debiasing tool, recovering a meaningful share of bias-induced errors while preserving most correct answers across all instruct families. Cue-induced bias is therefore best understood not as a single flaw in LLMs but as a family of distinct, causally active directions that alignment tuning installs.