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arXiv · 2311.13541

Linear Log-Normal Attention with Unbiased Concentration

Yury Nahshan·Joseph Kampeas·Emir Haleva
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Abstract

Transformer models have achieved remarkable results in a wide range of applications. However, their scalability is hampered by the quadratic time and memory complexity of the self-attention mechanism concerning the sequence length. This limitation poses a substantial obstacle when dealing with long documents or high-resolution images. In this work, we study the self-attention mechanism by analyzing the distribution of the attention matrix and its concentration ability. Furthermore, we propose instruments to measure these quantities and introduce a novel self-attention mechanism, Linear Log-Normal Attention, designed to emulate the distribution and concentration behavior of the original self-attention. Our experimental results on popular natural language benchmarks reveal that our proposed Linear Log-Normal Attention outperforms other linearized attention alternatives, offering a promising avenue for enhancing the scalability of transformer models.

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Yury Nahshan, Joseph Kampeas, Emir Haleva. 2023-11-22. Linear Log-Normal Attention with Unbiased Concentration. https://arxiv.org/abs/2311.13541

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