arXiv Computation and Language

Putting Transformer Theories to the Test

arXiv Machine Learning
Oct 16

Can Capability Enhancement be Localized?

The paper investigates whether removing a small set of attention heads in transformer-based language models can improve task performance, a phenomenon termed Capability Enhancement Localization (CEL). Empirical experiments across various models identify sparse head combinations whose ablation boosts performance without fine-tuning. The authors also provide a theoretical explanation using a simplified attention model, showing that training dynamics can concentrate conflicting task features into specific heads, whose removal selectively benefits one task while harming another.

By Anh Tuan Nguyen, Anna Bair, Zico Kolter