Phonetic and Graphemic Systems for Multi-Genre Broadcast Transcription
Table 6: %WER of the final MGB-3 system on dev17b.
['Model', 'Model', 'Comb tg', 'Ph/Gr Comb tg', 'Ph/Gr Comb fg', 'Ph/Gr Comb +rnn']
Given the small difference between the phonetic and graphemic ensembles, additional gains from combining the systems might be expected. However, the extensive use of combination techniques means that diversity between these ensembles has already been significantly reduced. At this point, it is interesting to see if improved language modelling approaches can yield further benefits. The RNNLM gave an additional improvement yielding a final error rate of 17.9% on this task.