LING 6520: Comparative Topics in Linguistics (from a computational perspective)Martha Palmer
Jan 15, 2008
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What does Linguistics offer Computational Lexical Semantics?
What does Computational Lexical Semantics offer Linguistics?
What can we do together?
Linguistics → CLS
• Syntactic structure – dependencies• Jackendoff
– Lexical Conceptual Structures• Fillmore, Talmy, Dowty, ….
– Case frames, conceptual analyses, proto-roles,….• Levin’s English verb classes
– Other languages?• Lexicographic sense distinctions• Discourse structure• Event representations
CLS → Linguistics
• Quantitative analysis of data– Frequency counts, mutual information, automatic
clustering, new & varied classifications– Word co-occurrences, subcat frame distributions, pp
attachment preferences, word alignments– tomorrow
• Grammatical formalisms – TAG’s, LFG’s, CCG’s, HPSG’s– Alternative building blocks for human sentence
processing – models of regular sense extensions
Feature-based Lexicalized Tree-Adjoining Grammars
Joshi,et al 75, Joshi 85,
• Elementary trees – Initial trees– Auxiliary trees
• Two operations– Substitution– Adjunction
Same event - different syntactic frames
John broke windows. SUBJ VERB OBJ
Windows broke. SUBJ VERB
Syntactic Parses
Elementary Trees
SubstitutionS
V
NP↓
NP↓
VP
break
NP
John
NP
the
Ndet
window
SubstitutionS
V
NP↓
NP↓
VP
break
NP
John
NP↓
the
Ndet
window
Derived TreeS
V
NP↓
NP ↓
VP
John
the
Nbreak
det
window
Feature-based SubstitutionS
V
NP↓
NP↓
VP+sing +past
break
NP+sing
John
NP
the
Ndet
window
4/1/04
Derived Tree w/ FeaturesS
V
NP+sing
NP↓
VP +sing +past
John
the
Nbreak
det
window
4/1/04
AdjunctionS
V
NP↓
NP↓
VP
John
the
Nbreak
det
window
VP
quickly
VP *Adv
4/1/04
Adjunction (cont.)S
NP↓
JohnV
VP *
break
NP↓
the
Ndet
window
VP
quickly
Adv
4/1/04
Extending Senses Through Adjunction