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arXiv · 2407.07239

RotRNN: Modelling Long Sequences with Rotations

Kai Biegun·Rares Dolga·Jake Cunningham·David Barber
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Abstract

Linear recurrent neural networks, such as State Space Models (SSMs) and Linear Recurrent Units (LRUs), have recently shown state-of-the-art performance on long sequence modelling benchmarks. Despite their success, their empirical performance is not well understood and they come with a number of drawbacks, most notably their complex initialisation and normalisation schemes. In this work, we address some of these issues by proposing RotRNN -- a linear recurrent model which utilises the convenient properties of rotation matrices. We show that RotRNN provides a simple and efficient model with a robust normalisation procedure, and a practical implementation that remains faithful to its theoretical derivation. RotRNN also achieves competitive performance to state-of-the-art linear recurrent models on several long sequence modelling datasets.

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Kai Biegun, Rares Dolga, Jake Cunningham, David Barber. 2024-07-09. RotRNN: Modelling Long Sequences with Rotations. https://arxiv.org/abs/2407.07239

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