Putting it Together
• Three models
– language bigram à P(word(i)|word(i-1))
– word pronunciation HMM à P(phones|word)
– phone HMM à P(signal|phone)
• To compute P(words|signal), these need to be
combined.
• One big HMM – make language bigram into an
HMM and construct a large HMM by nesting each
level of abstraction