Log-linear model combination with word-dependent scaling factors
Björn Hoffmeister, Ruoying Liang, Ralf Schlüter, Hermann Ney · 2009
Log-linear model combination is the standard approach in LVCSR to combine several knowledge sources, usually an acoustic and a language model.Instead of using a single scaling factor per knowledge source, we make the scaling factor wordand pronunciation-dependent.In this work, we combine three acoustic models, a pronunciation model, and a language model for a Mandarin BN/BC task.The achieved error rate reduction of 2% relative is small but consistent for two test sets.An analysis of the results shows that the major contribution comes from the improved interdependency of language and acoustic model.