Improving LSTM-CTC based ASR performance in domains with limited training data
Table 7: Experiments with dropout on recurrent connections. Postfix step and sequence indicates whether dropout mask is sampled every time step or every sequence. Recurrent dropout without memory loss is abbreviated as no memory loss (NML) dropout.
['System', '%WER ( [ITALIC] dev-clean)']
From the table it is clear that application of dropout for recurrent connections is indeed beneficial. In line with our expectations, NML dropout worked better than RNNDrop with the per sequence For the NML dropout variants we see relative WER reductions over 20% compared to the corresponding baseline, or ∼13% relative WER reduction compared to the prior best system without dropout WER of 9.78%.