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arXiv · 2609.28117

Scaling Attention Head Analysis via Gradient-Based Attribution in Context-Aware Machine Translation

Paweł Mąka·Yusuf Can Semerci·Jan Scholtes·Gerasimos Spanakis
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Abstract

In this paper, we introduce a gradient-based head attribution strategy where the Token-level Max-Margin loss is backpropagated to the attention maps. This framework enables a large-scale causal analysis of attention heads, making it suitable for LLMs. We evaluate our method on the task of disambiguation in Context-aware Machine Translation, where we analyze 50 phenomena across 4 models and 4 language directions. We empirically show the alignment of our method with the effects of increasing the attention scores of token-to-token relations on three models and two language directions, ensuring the robustness of our method. Our analysis reveals the presence of the "general-purpose" attention heads that improve the model's performance when attending to different relations. We find that the average attention a head assigns to a relation does not necessarily relate to the model's performance, which suggests that the models developed redundancies during training in terms of the head functions.

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Paweł Mąka, Yusuf Can Semerci, Jan Scholtes, Gerasimos Spanakis. 2026-09-23. Scaling Attention Head Analysis via Gradient-Based Attribution in Context-Aware Machine Translation. https://arxiv.org/abs/2609.28117

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