collaborators

7 papers

cs.CL2026

Steering Instruction Hierarchies at Inference Time

Siqi Zeng, Sewoong Lee, Han Zhao +1

The paper proposes V‑Steer, a training‑free method that modifies cached value vectors during inference to ensure higher‑priority prompts (like system prompts) override lower‑priori…

cs.LG2026

Task Vector Bases: A Unified and Scalable Framework for Compressed Task Arithmetic

Siqi Zeng, Yifei He, Meitong Liu +5

Task arithmetic, representing downstream tasks through linear operations on task vectors, has emerged as a simple yet powerful paradigm for transferring knowledge across diverse se…

cs.LG2026

Convex Dataset Valuation for Post-Training

Siqi Zeng, Christopher Jung, Rui Li +7

Improving LLM performance on downstream tasks sometimes requires leveraging auxiliary datasets during post-training. In practice, however, developers face constraints on compute, l…

cs.CL2025

Who is In Charge? Dissecting Role Conflicts in Instruction Following

Siqi Zeng

Large language models should follow hierarchical instructions where system prompts override user inputs, yet recent work shows they often ignore this rule while strongly obeying so…

cs.LG2025

When LRP Diverges from Leave-One-Out in Transformers

Weiqiu You, Siqi Zeng, Yao-Hung Hubert Tsai +2

Leave-One-Out (LOO) provides an intuitive measure of feature importance but is computationally prohibitive. While Layer-Wise Relevance Propagation (LRP) offers a potentially effici…

cs.LG2025

MergeBench: A Benchmark for Merging Domain-Specialized LLMs

Yifei He, Siqi Zeng, Yuzheng Hu +3

Model merging provides a scalable alternative to multi-task training by combining specialized finetuned models through parameter arithmetic, enabling efficient deployment without t…