Light Recurrent Unit: Towards an Interpretable Recurrent Neural Network for Modeling Long-Range Dependency

Recurrent neural networks (RNNs) play a pivotal role in natural language processing and computer vision. Long short-term memory (LSTM), as one of the most representative RNNs, is built upon relatively complex architecture with an excessive number of parameters, which results in large storage, high training cost, and lousy interpretability. In this paper, we propose a lightweight network called Light Recurrent Unit (LRU). On the one hand, we designed an accessible gate structure, which has high interpretability and addresses the issue of gradient disappearance. On the other hand, we introduce the Stack Recurrent Cell (SRC) structure to modify the activation function, which not only expedites convergence rates but also enhances the interpretability of the network. Experimental results show that our proposed LRU has the advantages of fewer parameters, strong interpretability, and effective modeling ability for variable length sequences on several datasets. Consequently, LRU could be a promising alternative to traditional RNN models in real-time applications with space or time constraints, potentially reducing storage and training costs while maintaining high performance.