Title
INTERNAL LANGUAGE MODEL TRAINING FOR DOMAIN-ADAPTIVE END-TO-END SPEECH RECOGNITION
Abstract
The efficacy of external language model (LM) integration with existing end-to-end (E2E) automatic speech recognition (ASR) systems can be improved significantly using the internal language model estimation (ILME) method [1]. In this method, the internal LM score is subtracted from the score obtained by interpolating the E2E score with the external LM score, during inference. To improve the ILME-based inference, we propose an internal LM training (ILMT) method to minimize an additional internal LM loss by updating only the E2E model components that affect the internal LM estimation. ILMT encourages the E2E model to form a standalone LM inside its existing components, without sacrificing ASR accuracy. After ILMT, the more modular E2E model with matched training and inference criteria enables a more thorough elimination of the source-domain internal LM, and therefore leads to a more effective integration of the target-domain external LM. Experimented with 30K-hour trained recurrent neural network transducer and attention-based encoder-decoder models, ILMT with ILME-based inference achieves up to 31.5% and 11.4% relative word error rate reductions from standard E2E training with Shallow Fusion on out-of-domain LibriSpeech and in-domain Microsoft production test sets, respectively.
Year
DOI
Venue
2021
10.1109/ICASSP39728.2021.9415039
2021 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING (ICASSP 2021)
Keywords
DocType
ISSN
Speech recognition, language model, recurrent neural network transducer, attention-based encoder-decoder
Conference
2021 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Toronto, Canada
Citations 
PageRank 
References 
0
0.34
15
Authors
9
Name
Order
Citations
PageRank
Zhong Meng13314.95
Naoyuki Kanda210319.45
Yashesh Gaur3159.06
Sarangarajan Parthasarathy4465.57
Sun Eric543.11
Liang Lu6894165.81
Xie Chen734825.74
Jinyu Li891572.84
Yifan Gong91332135.58