Recurrent Neural Networks (RNNs) have dominated language modeling because of their superior performance over traditional N-gram based models. In many applications, a large Recurrent Neural Network language model (RNNLM) or an ensemble of several RNNLMs is used. These models have large memory footprints and require heavy computation. In this paper, we examine the effect of applying knowledge distillation in reducing the model size for RNNLMs. In addition, we propose a trust regularization method to improve the knowledge distillation training for RNNLMs. Using knowledge distillation with trust regularization, we reduce the parameter size to a third of that of the previously published best model while maintaining the state-of-the-art perplexity result on Penn Treebank data. In a speech recognition N-bestrescoring task, we reduce the RNNLM model size to 18.5% of the baseline system, with no degradation in word error rate(WER) performance on Wall Street Journal data set.

本文通过应用知识蒸馏和信任正则化方法来减小模型大小，从而降低了循环神经网络（RNN）语言模型的计算成本，并保持了该模型在Penn Treebank数据集上的最先进困惑度结果，同时在声音识别任务中没有降低单词错误率（WER）。

循环神经网络语言建模的知识蒸馏与信任正则化