Papers › Long Expressive Memory for Sequence Modeling

Long Expressive Memory for Sequence Modeling

10 Oct 2021ICLR 2022 4arXiv:2110.04744archive 2025-07-28

T. Konstantin Rusch, Siddhartha Mishra, N. Benjamin Erichson, Michael W. Mahoney

We propose a novel method called Long Expressive Memory (LEM) for learning long-term sequential dependencies. LEM is gradient-based, it can efficiently process sequential tasks with very long-term dependencies, and it is sufficiently expressive to be able to learn complicated input-output maps. To derive LEM, we consider a system of multiscale ordinary differential equations, as well as a suitable time-discretization of this system. For LEM, we derive rigorous bounds to show the mitigation of the exploding and vanishing gradients problem, a well-known challenge for gradient-based recurrent sequential learning methods. We also prove that LEM can approximate a large class of dynamical systems to high accuracy. Our empirical results, ranging from image and time-series classification through dynamical systems prediction to speech recognition and language modeling, demonstrate that LEM outperforms state-of-the-art recurrent neural networks, gated recurrent units, and long short-term memory models.

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LEMCell tk-rusch/lem/src/Google12/network.py official repository ran · metamorphic tier: deterministic no licence file found · pointer only · 9cfb904b319e5586 · report
evaluate_deterministic deepmind/lamb/lamb/evaluation.py found in paper text by Syntology unverified Apache-2.0 (permissive) · 2c67d2b0758d5fe0 · report
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Tasks

Language ModelingLanguage ModellingSequential Image ClassificationSpeech RecognitionTime SeriesTime Series AnalysisTime Series Classificationspeech-recognition

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Sequential Image Classification Sequential MNIST LEM Permuted Accuracy 96.6% #18 of 30 Archive leaderboard report
Sequential Image Classification Sequential MNIST LEM Unpermuted Accuracy 99.5% #18 of 30 Archive leaderboard report
Sequential Image Classification noise padded CIFAR-10 LEM % Test Accuracy 60.5 #3 of 7 Archive leaderboard report
Time Series Classification EigenWorms LEM % Test Accuracy 92.3 #1 of 8 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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