Hierarchical Softmax for End-to-End Low-resource Multilingual Speech Recognition

TL;DR

This paper introduces a multilingual hierarchical Softmax approach that leverages neighboring languages' similarities to improve low-resource speech recognition accuracy and efficiency.

Contribution

It proposes a novel hierarchical Softmax decoding method based on linguistic unit similarities across languages for low-resource speech recognition.

Findings

Improved recognition accuracy in low-resource settings

Enhanced decoding efficiency

Effective cross-lingual knowledge sharing

Abstract

Low-resource speech recognition has been long-suffering from insufficient training data. In this paper, we propose an approach that leverages neighboring languages to improve low-resource scenario performance, founded on the hypothesis that similar linguistic units in neighboring languages exhibit comparable term frequency distributions, which enables us to construct a Huffman tree for performing multilingual hierarchical Softmax decoding. This hierarchical structure enables cross-lingual knowledge sharing among similar tokens, thereby enhancing low-resource training outcomes. Empirical analyses demonstrate that our method is effective in improving the accuracy and efficiency of low-resource speech recognition.