On maximum mutual information speaker-adapted training

In this work, we combine maximum mutual information-based parameter estimation with speaker-adapted training (SAT). As will be shown, this can be achieved by performing unsupervised parameter estimation on the test data, a distinct advantage for many recognition tasks involving conversational speech. We also propose an approximation to the maximum likelihood and maximum mutual information SAT re-estimation formulae that greatly reduces the amount of disk space required to conduct training on corpora such as Broadcast News, which contains speech from thousands of speakers. We present the results of a set of speech recognition experiments on three test sets: the English Spontaneous Scheduling Task corpus, Broadcast News, and a new corpus of Meeting Room data collected at the Interactive Systems Laboratories of the Carnegie Mellon University.