19 Nov
1999
Sphinx
Speech Group, CMU-SCS (rkm@cs.cmu.edu)
Word Segmentation Problem (contd.)
·Tree
lexicon:
·At
A: root node
for ninety entered
without any LM score
·At
B: Attempt to
enter root node for ninety again
·Transition
may or may not succeed (no LM score used)
·At
C: obtain LM
score for ninety
w.r.t. all predecessors
·If transition at B failed, the only candidate
predecessor is ninety;
result:
incorrect segmentation for ninety(2), incorrect recognition
nineteen
ninety
ninety
ninety
nineteen
ninety
ninety
correct segmentation for ninety
incorrect segmentation for ninety
Assume P (ninety | nineteen) > P (ninety | ninety).
Decision points: A B C