arXiv Computation and Language By Anssi Moisio, Mathias Creutz, Mikko Kurimo

Type Diversity Enables Transformers to Generalise Compositionally

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The paper investigates why Transformers struggle more with structural than lexical compositional generalisation. It argues that this disparity stems from low structural type diversity rather than an inherent limitation of Transformers. By creating linguistically diverse variants of the COGS and SLOG datasets, the authors show that type diversity correlates equally with generalisation in both lexical and structural cases, challenging previous explanations of the difficulty.

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