Development Of The 2008 Sri Mandarin Speech-To-Text System For Broadcast News And Conversation

We describe the recent progress in SRI's Mandarin speech-to-text system developed for 2008 evaluation in the DARPA GALE program. A data-driven lexicon expansion technique and language model adaptation methods contribute to the improvement in recognition performance. Our system yields 8.3% character error rate on the GALE dev08 test set, and 7.5% after combining with RWTH systems. Compared to our 2007 evaluation system, a significant improvement of 13% relative has been achieved.