Information for a word recognized by the speech
recognizer.
Time offset relative to the beginning of the audio that
corresponds to the start of the spoken word. This is an
experimental feature and the accuracy of the time offset can
vary.
The Speech confidence between 0.0 and 1.0 for this word. A
higher number indicates an estimated greater likelihood that
the recognized word is correct. The default of 0.0 is a
sentinel value indicating that confidence was not set. This
field is not guaranteed to be fully stable over time for the
same audio input. Users should also not rely on it to always
be provided.