Transcript What you have learne..

What you have learned
and how you can use it
11-721: Grammars and Lexicons
Parts I-III
Linguistic Tests:
what you have learned
• Tests can be used to make consistent
decisions with higher inter-coder
agreement than guesses or intuition.
• Some specific tests that you can use for
parts-of-speech and constituency in
English.
Linguistic Tests:
What you can use it for
• Annotating corpora
• Evaluating the quality of an annotated
corpus
How languages differ
What you have learned
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Parts of speech
Coding properties of grammatical relations
Word order of S, O, and V
Word order of old and new information
Relative clauses
Passive
Control constructions:
– Coding as matrix subject/object
– Control of adjunct clauses
How languages differ
What you can use it for
• Any language technology system should be portable to
any human language
• Interlingua for machine translation
– Must abstract away from the surface differences between
languages
• Word alignment algorithms:
– Take into account the encoding of grammatical relations and old
and new information.
• A language you don’t speak is no longer a black box to
you.
– You can work on language technologies systems for langauges
that you do not speak.
– Of course you will need to work with someone who speaks it
– Evaluate, do error-analysis, and trouble-shoot
• DARPA tides Chinese and Arabic: most groups were working blind
using only BLEU scores to guide system development
What languages have in common
What you have learned
• Grammatical relations
• Old and new information
• Semantic roles
What languages have in common
How you can use it
• Design language technologies applications
that streamline the parts that are common
across languages:
– Your English parser will not be totally different
from your Hungarian parser.
Lexical Functional Grammar
What you have learned
• Encoding of grammatical relations in constituent
structure
– Language variation
• Functional structure:
– Independent of word order and grammatical encoding
• Lexical Mapping:
– How to assign semantic roles to noun phrases
• A formalism for describing human language syntax that
can be used by a parser.
• Some ways of formalizing some rules for English syntax:
– Active and passive sentences, matrix coding as subject/object,
control by matrix subject/object, auxiliary verbs, negation,
embedded clauses.
Lexical Functional Grammar
What you can use it for
• Write grammars for any language using
the Tomita parser and GenKit
• Design your own parser that:
– Maps noun phrases onto semantic roles
– Accounts for differences in encoding of
grammatical relations
– Accounts for similarities in behavior of
grammatical relations
What you can do next
• Language Technolgies for Computer Assisted
Language Learning
– Spring 2005
– Build three CALL systems using
• speech recognition, parsing, pattern matching on trees
• Grammar Formalisms
– Spring 2006
– Learn more about LFG and other grammar
formalisms
• HPSG, TAG, Dependency Grammar, Categorial Grammar
– See how the pieces can be put together in different
ways  get a deeper understanding of what human
language is and what an LT system has to do.
What you can do next
• Formal Semantics
– Spring 2006
• Machine Translation and MT Lab
– Spring 2005
• Linguistics courses at University of
Pittsburgh
– Phonetics, Phonology, Syntax, Morphology,
Field Methods