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PART|I Signal Processing, Modelling and Related Mathematical Tools
characteristics, both affecting the acoustic models. Obviously, faster
speaking rates also result in more frequent and stronger pronunciation
changes. Over-articulation is the opposite case and causes some trou-
ble too. It’s been reported that when users are speaking slower and
emphasise all syllables, as when making a slow dictation, they notice
that the ASR system does not recognise their words properly. This
only increases the problem, as acoustic models are often being trained
using ‘regular’ speech. Emotions are also becoming a hot topic, as
they can indeed have a negative effect ...