Lecture 11 - Natural Language Processing

• Layers
• acoustics and graphics
• ASR + OCR state of the art
• telephone quality speech, LPC model vs cochlea model
• continuous speech - no word boundaries, DTW, badaga experiment
• handwriting
• syntax (see PROLOG example below)
• semantics
• The man cried fire the gun maker.
• pragmatics
• How do you wreck a nice beach?
• syntax parsing in PROLOG
• sentence([the,boy,eats,an,apple]). yes
• sentence(S) :- append(N,V,S), subject_phrase(N), intransitive_verb_phrase(V).
• sentence(S) :- append3(N,V,O,S), subject_phrase(N), transitive_verb_phrase(V), object_phrase(O).
• subject_phrase(N) :- noun(N).
• subject_phrase(P) :- append(A,N,P), article(A), noun(N).
• subject_phrase(P) :- append3(A,D,N,P), article(A), adjective(D), noun(N).
• subject_phrase(P) := pronoun(P).
• intransitive_verb_phrase(V) := intransitive_verb(V).
• intransitive_verb_phrase(P) :- append(A,V,P), adverb(A), intransitive_verb(V).
• noun([apple]).
• noun([banana]).
• extensions - tenses, plurals, conjugation
• there are very good such systems today
• disambiguization - eg. pronoun reference problem
• automatic translation interlingua, translating telephone - Janus
• call routing and database query (Al Gorin) no separation of acoustic layer
• automatic acquisition of language (Tishby and Pereira)