Verifying LVCSR Output at Different Levels with Generalized Posterior Probability

Generalized posterior probability (GPP), a statistical confidence measure, is used for verification of large vocabulary continuous speech recognition (LVCSR) output at subword, word and utterance levels. GPP is obtained by combining exponentially and optimally weighted products of acoustic and language model scores for reappeared units in the reduced search space (e.g., word graph). Experimental results have demonstrated the effectiveness of GPP for verifying LVCSR output at all three levels. Keyword confidence measure, posterior probability, large vocabulary continuous speech recognition 1 The author is now with Microsoft Research Asia.