Phone recognition with deep sparse rectifier neural networks

Rectifier neurons differ from standard ones only in that the sigmoid activation function is replaced by the rectifier function, max(0, x). This modification requires only minimal changes to any existing neural net implementation, but makes it more effective. In particular, we show that a deep architecture of rectifier neurons can attain the same recognition accuracy as deep neural networks, but without the need for pre-training. With 4-5 hidden layers of rectifier neurons we report 20.8% and 19.8% phone error rates on TIMIT (with CI and CD units, respectively), which are competitive with the best results on this database.