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ETAP-3: State of the Art, Options, and Prospects of Development. Leonid Iomdin Institute for Information Transmission Problems Russian Academy of Sciences iomdin @iitp.ru. Theoretical Background. I gor Mel’ č uk: «Meaning Text» theory J u rij Apresjan: - PowerPoint PPT Presentation
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ETAP-3: State of the Art, Options, and Prospects of Development
Leonid IomdinInstitute for Information Transmission
Problems
Russian Academy of Sciences
Prague, May 12, 2008
Theoretical Background
Igor Mel’čuk:
«Meaning Text» theoryJurij Apresjan:
Integrated Theory of Linguistic Description and Systemic lexicography
Prague, May 12, 2008
ETAP-3 Options
Machine translation SynTagRus: the tagged corpus of
Russian Texts Generation from and to UNL (Quasi)synonymous Paraphrasing Computer-Aided Language Learning
Tool
Prague, May 12, 2008
Machine Translation
Russian English• 120,000-strong morphological dictionaries
• 95,000-strong combinatorial dictionaries Russian German prototype Russian French prototype Russian Korean prototype Russian Spanish prototype Arabic English prototype
Prague, May 12, 2008
Major Features of ETAP Environment
Rule-based Approach Stratificational Approach Syntactic Dependencies Lexicalistic Approach Self-Tuning Maximum Reusability of Linguistic
resources
Prague, May 12, 2008
General Layout of Translation Process
OBJECTS STAGES DICTIONARIES
Sourcephrase
Expansion
Morphologicalanalysis
Source morphologicaldictionary
Sourcecombinatorial
dictionary
Parsing
MorphSsource
SyntSsource Normalization
NormSsource Transfer
Targetcombinatorial
dictionary
NormStarget
SyntStarget Syntactic
synthesis
Morphologicalsynthesis
Target morphologicaldictionaryTarget
phrase
MorphStarget
Prague, May 12, 2008
Dependency Syntactic Structure
They made a general remark that it was true.
Prague, May 12, 2008
Self-Tuning: Grammar vs. Dictionary
General regularities: general rules that apply to very large classes of words and occur very often.• Example: agreement Adj + N
Restricted-scope regularities: specific rules that apply to restricted classes of words and have limited occurrence. • Example: compound numerals
Prague, May 12, 2008
Multiple Translation
They made a general remark that …
• (a) ‘they remarked in a general way that…’
• (b) ‘they forced a general to remark that…’
Prague, May 12, 2008
Synonymous Paraphrasing
The director ordered John to write a report
The director gave John an order to write a report
John was ordered by the director to write a report
John received an order from the director to write a report
Prague, May 12, 2008
Lexical Functions
Substitute LF• synonyms, antonyms, converse terms,
derivatives
Collocate LF• MAGN = 'a high degree of what is denoted
by X’
• OPER/FUNC
• ...
Prague, May 12, 2008
Lexical Functions
MAGN disease grave MAGN fog heavy MAGN control strict
Prague, May 12, 2008
Oper / Func Family of LF
INVITATION
the minister the ambassador
1 issues
receives
2
Prague, May 12, 2008
Examples of LF Oper
Oper1 (invitation) = issue
Oper2 (invitation) = receive
Oper1 (defeat) = suffer
Oper2 (resistence) = encounter
Oper2 (respect) = enjoy
Prague, May 12, 2008
Examples of LF Func
Func1 (fear) = possess
Func2 (decision) = concern
Func1 (responsibility) = rest (with)
Func2 (vengeance) = fall (upon)
Prague, May 12, 2008
General Properties of Lexical Functions
Universality Intralinguistic idiomaticity
• grave disease, heavy fog
• *heavy disease, *grave fog.
Cross-linguistic idiomaticity• Rus. тяжелая болезнь ‘heavy disease’
• Rus. густой туман ‘dense fog’
Prague, May 12, 2008
General Properties of Lexical Functions (cont.)
Paraphrasing Potential:
• He respects [X] his teachers
• He has [OPER1 (S0 (X))] respect [S0 (X)] for his teachers
• He treats [LABOR12 (S0 (X))] his teachers with respect
• His teachers enjoy [OPER2 (S0 (X))] his respect
Prague, May 12, 2008
LF in Practical Applications
Syntactic and Lexical Ambiguity Resolution in Parsers
Idiomatic Translation of a Large Class of Set Expressions in Machine Translation
Sentence Paraphrasing
Prague, May 12, 2008
Lexical Ambiguity Resolution
to draw a distinction - provodit' razlichie Both verbs are extremely ambiguous:
• draw - more than 50 meanings
• provodit’ - more than 10 meanings
Prague, May 12, 2008
Syntactic Ambiguity Resolution
support of the parliament • 'support by the parliament'
• 'support (given) to the parliament'
The president had [Y=OPER2(X)] the support [X] of the parliament
The fear [X] of his wife possessed [Y = FUNC1 (X)] Peter
The fears of his wife infected Peter.
Prague, May 12, 2008
Idiomatic translation: LF Temp
March: in - март: в2 Tuesday: on - вторник: в1 dawn: at - рассвет: на2 moment: at - момент: в1 Easter: at – пасха: на1
Prague, May 12, 2008
Sentence Paraphrasing X = CONV12 (X)
This group consists of 20 persons –
Twenty persons comprise this group;
X + Y = ANTI1(X) + ANTI2(Y) He began to observe the rules –
He stopped violating the rules
X = LABOR12 + S0(X) He respects his parents –
He treats his parents with respect
Prague, May 12, 2008
Sample Dictionary Entry (Excerpt): CHANCE
CHANCE1
POR:S
SYNT:COUNT,PREDTO,PREDTHAT
DES:'FACT','ABSTRACT’
Prague, May 12, 2008
CHANCE
D1.1:OF,'PERSON'
D2.1:OF,'FACT'
D2.2:TO2
D2.3:THAT1
Prague, May 12, 2008
CHANCE
SYN1: OPPORTUNITY
MAGN: GOOD1, FAIR1, EXCELLENT
ANTIMAGN: SLIGHT, SLIM, POOR, LITTLE1, SMALL
OPER1: HAVE, STAND1
REAL1-M: TAKE
Prague, May 12, 2008
CHANCE
ANTIREAL1-M: MISS1
INCEPOPER1: GET
FINOPER1: LOSE
CAUSFUNC1: GIVE <TO1>
ZONE:R
TRANS:ШАНС/СЛУЧАЙ
Prague, May 12, 2008
CHANCE
REG:TRADUCT2.00TAKE:XLOC:RR:COMPOS/MODIF/POSSESCHECK1.1 DEP-LEXA(X,Z,PREPOS,BY1)N:01CHECK1.1 DOM(X,*,R)DO1 ZAMRUZ:Z(PO1)2 ZAMRUZ:X(SLUCHAJNOST’)
Prague, May 12, 2008
CHANCE
N:02CHECK2.1 DOM(X,*,*)DO1 ZAMRUZ:Z(SLUCHAJNO)2 STERUZ:X
TRAF:RA-EXPANS.16LA:THAT1
TRAF:RA-EXPANS.22
Prague, May 12, 2008
What is UNL?
UNL is a formal language for meaning representation
A minimal unit of UNL is a UNL expression
UNL expression corresponds to a sentence of natural language in the amount of information conveyed
Prague, May 12, 2008
Internet
UNL Architecture
French People
Hindu PeopleSpanish People
Chinese PeopleFrenchChine
se
Spanish
UNL System
Hindi
Prague, May 12, 2008
How is UNL made?
UNL is a formal language of meaning representation
A minimum UNL unit is UNL graph The amount of sense rendered by a UNL
graph corresponds to a natural language sentence
Prague, May 12, 2008
Two MT architectures: Transfer vs. Interlingua
Source text Target text
Interlingua
Transfer
Prague, May 12, 2008
UNL approach to lexical design
Semantic units of UNL (universal words, UW) are designed on the basis of natural language (English) words which can be semantically modified if need be
Prague, May 12, 2008
UNL strategy
Lexical meanings of the natural language are represented by UWs.
1. Lexical meaning coincides with the meaning of an unambiguous English word
2. Lexical meaning coincides with one of the senses of an unambiguous English word
3. Lexical meaning does not coincide with any of the lexical meanings of English
Prague, May 12, 2008
Disambiguation of natural word senses
Coach: bus, trainer, train, drill,...• coach(icl>bus>transport)
• сoach(icl>person,obj>sportsman)
• coach(icl>do,obj>sportsman)
• coach(icl>do,obj>student)
Prague, May 12, 2008
прибежатьприлететь приплыть приползтиcome(met>run)come(met>plane)come(met>swim)come(met>crawl)
Formation of new UWs
Prague, May 12, 2008
Formation of new UWs
жениться marry(agt>man)выходить замуж marry(agt>woman)