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PART|I Signal Processing, Modelling and Related Mathematical Tools
words or uncertain recognition due to the background noise in the
audio or else to perform word spotting (recognition of a limited num-
ber of keywords in an audio stream, generally without using any LM).
These are obviously important concepts when the ASR is considered
as a component in a larger multimodal dialog system, where the out-
comes from different modalities can be better integrated using such
confidence measures. Confidence measures are also extremely useful
in dialogue systems, potentially guiding it towards a less frustrating
experience, especially when there is a need to ...