Acoustically grounded word embeddings for improved acoustics-to-word speech recognition
Table 2: Cross-view word discrimination performance, measured via average precision (AP), of acoustically grounded word embeddings (AGWE) and CTC-based embeddings (prediction layer weights).
['Vocab', 'AGWE', 'CTC Baseline', 'CTC Initialized', 'CTC Regularized']
The significantly better AP of AGWE shows that they capture discriminative information that is not discovered implicitly by CTC training. By using these pre-trained embeddings to initialize our model or regularize CTC training, the prediction layer is better able to retain this word discrimination ability.