arXiv Machine Learning By Aryan Sharma, Cutter Dawes, Shivam Raval

Dissociating Decodability and Causal Use in Bracket-Sequence Transformers

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arXiv:2604. 22128v2 Announce Type: replace-cross Abstract: When trained on tasks requiring an understanding of hierarchical structure, transformers have been found to represent this hierarchy in distinct ways: in the geometry of the residual stream, and in stack-like attention patterns maintaining a last-in, first-out ordering.

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Your Transformer Can Hold Two Thoughts at Once: Evidence of Linear Superposition in LLMs

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An expressivity analysis of hierarchical modelling in deep transformers via bounded-depth grammars

arXiv:2606. 17522v1 Announce Type: cross Abstract: Deep neural networks are widely believed to derive their expressive power from their ability to form \textbf{hierarchical representations}, capturing progressively more abstract and compositional features across layers.

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