Papers › UnICORNN: A recurrent model for learning very long time dependencies

UnICORNN: A recurrent model for learning very long time dependencies

9 Mar 2021arXiv:2103.05487archive 2025-07-28

T. Konstantin Rusch, Siddhartha Mishra

The design of recurrent neural networks (RNNs) to accurately process sequential inputs with long-time dependencies is very challenging on account of the exploding and vanishing gradient problem. To overcome this, we propose a novel RNN architecture which is based on a structure preserving discretization of a Hamiltonian system of second-order ordinary differential equations that models networks of oscillators. The resulting RNN is fast, invertible (in time), memory efficient and we derive rigorous bounds on the hidden state gradients to prove the mitigation of the exploding and vanishing gradient problem. A suite of experiments are presented to demonstrate that the proposed RNN provides state of the art performance on a variety of learning tasks with (very) long-time dependencies.

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Tasks

Sentiment AnalysisSequential Image ClassificationTime Series AnalysisTime Series Classification

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Sentiment Analysis IMDb UnICORNN Accuracy 88.4 #39 of 49 Archive leaderboard report
Sequential Image Classification Sequential MNIST UnICORNN Permuted Accuracy 98.4 #7 of 30 Archive leaderboard report
Sequential Image Classification noise padded CIFAR-10 UnICORNN % Test Accuracy 62.4 #2 of 7 Archive leaderboard report
Time Series Classification EigenWorms UnICORNN % Test Accuracy 90.3 #2 of 8 Archive leaderboard report
Time Series Classification EigenWorms coRNN % Test Accuracy 86.7 #3 of 8 Archive leaderboard report
Time Series Classification EigenWorms IndRNN % Test Accuracy 49.7 #6 of 8 Archive leaderboard report
Time Series Classification EigenWorms expRNN % Test Accuracy 40.0 #8 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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