Table 6.

Performance of ASR systems with different end-to-end models.

Name	PER %
CTC	15.36
Attention	15.25
CTC_Attention ($\alpha =0.1$)	14.17
CTC_Attention ($\alpha =0.2$)	13.34
CTC_Attention ($\alpha =0.3$)	13.33
CTC_Attention ($\alpha =0.4$)	13.45
CTC_Attention ($\alpha =0.5$)	13.75
CTC_Attention ($\alpha =0.6$)	13.86
CTC_Attention ($\alpha =0.7$)	14.21
CTC_Attention ($\alpha =0.8$)	14.28
CTC_Attention ($\alpha =0.9$)	14.44
CTC_Attention ($\alpha$ dynamic adjustment)	13.01

Note: the phone segments marked wrong pronunciations by experts in the test set are ignored when the phone error rate (PER) of ASR is calculated.