Exploring Gaussian mixture model framework for speaker adaptation of deep neural network acoustic models
Table 6: Davies-Bouldin (DB) index for different types of features used in TDNN training. The DB index is calculated on lattice-based features produced by the corresponding model.
['Features', 'State 0', 'State 1', 'State 2']
(State 0, 1, 2). That confirms the fact that the clusters are better for adapted features. The acoustic model with the adapted GMMD features (BN⊕i-vectors⊕GMMD) shows the best result (the smallest value of DB index).