A Probabilistic Interpretation of Transformers

Alexander Shim

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arXiv · 2205.01080

A Probabilistic Interpretation of Transformers

Alexander Shim

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Abstract

We propose a probabilistic interpretation of exponential dot product attention of transformers and contrastive learning based off of exponential families. The attention sublayer of transformers is equivalent to a gradient ascent step of the log normalizer, which is the log-sum-exp term in the Hopfield theory of attention. This ascent step induces a parallel expansion of points, which is counterbalanced by a contraction from layer normalization. We also state theoretical limitations of our theory and the Hopfield theory and suggest directions for resolution.

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Alexander Shim. 2022-04-28. A Probabilistic Interpretation of Transformers. https://arxiv.org/abs/2205.01080

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