Title
Auto-encoder bottleneck features using deep belief networks
Abstract
Neural network (NN) bottleneck (BN) features are typically created by training a NN with a middle bottleneck layer. Recently, an alternative structure was proposed which trains a NN with a constant number of hidden units to predict output targets, and then reduces the dimensionality of these output probabilities through an auto-encoder, to create auto-encoder bottleneck (AE-BN) features. The benefit of placing the BN after the posterior estimation network is that it avoids the loss in frame classification accuracy incurred by networks that place the BN before the softmax. In this work, we investigate the use of pre-training when creating AE-BN features. Our experiments indicate that with the AE-BN architecture, pre-trained and deeper NNs produce better AE-BN features. On a 50-hour English Broadcast News task, the AE-BN features provide over a 1% absolute improvement compared to a state-of-the-art GMM/HMM with a WER of 18.8% and pre-trained NN hybrid system with a WER of 18.4%. In addition, on a larger 430-hour Broadcast News task, AE-BN features provide a 0.5% absolute improvement over a strong GMM/HMM baseline with a WER of 16.0%. Finally, system combination with the GMM/HMM baseline and AE-BN systems provides an additional 0.5% absolute on 430 hours over the AE-BN system alone, yielding a final WER of 15.0%.
Year
DOI
Venue
2012
10.1109/ICASSP.2012.6288833
Acoustics, Speech and Signal Processing
Keywords
Field
DocType
Gaussian distribution,belief networks,estimation theory,hidden Markov models,neural nets,AE-BN architecture,AE-BN features,English Broadcast News task,auto-encoder bottleneck features,deep belief networks,frame classification accuracy,middle bottleneck layer,neural network bottleneck features,posterior estimation network,pre-trained NN hybrid system,softmax,state-of-the-art GMM/HMM,Deep Belief Networks,Speech Recognition
Bottleneck,Autoencoder,Pattern recognition,Softmax function,Computer science,Deep belief network,Feature extraction,Speech recognition,Artificial intelligence,Hidden Markov model,Artificial neural network,Hybrid system
Conference
ISSN
ISBN
Citations 
1520-6149 E-ISBN : 978-1-4673-0044-5
978-1-4673-0044-5
67
PageRank 
References 
Authors
6.39
7
3
Name
Order
Citations
PageRank
Tara N. Sainath13497232.43
B. Kingsbury24175335.43
Bhuvana Ramabhadran31779153.83