ETAP-3: State of the Art, Options, and Prospects of Development Leonid Iomdin Institute for Information Transmission Problems Russian Academy of Sciences

ETAP-3: State of the Art, Options, and Prospects of Development

Leonid IomdinInstitute for Information Transmission

Problems

Russian Academy of Sciences

[email protected]

Prague, May 12, 2008

Theoretical Background

Igor Mel’čuk:

«Meaning Text» theoryJurij Apresjan:

Integrated Theory of Linguistic Description and Systemic lexicography


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


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


Major Features of ETAP Environment

Rule-based Approach Stratificational Approach Syntactic Dependencies Lexicalistic Approach Self-Tuning Maximum Reusability of Linguistic

resources


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


Dependency Syntactic Structure

They made a general remark that it was true.


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


Multiple Translation

They made a general remark that …

• (a) ‘they remarked in a general way that…’

• (b) ‘they forced a general to remark that…’


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


Lexical Functions

Substitute LF• synonyms, antonyms, converse terms,

derivatives

Collocate LF• MAGN = 'a high degree of what is denoted

by X’

• OPER/FUNC

• ...


Lexical Functions

MAGN disease grave MAGN fog heavy MAGN control strict


Oper / Func Family of LF

INVITATION

the minister the ambassador

1 issues

receives

2


Examples of LF Oper

Oper1 (invitation) = issue

Oper2 (invitation) = receive

Oper1 (defeat) = suffer

Oper2 (resistence) = encounter

Oper2 (respect) = enjoy


Examples of LF Func

Func1 (fear) = possess

Func2 (decision) = concern

Func1 (responsibility) = rest (with)

Func2 (vengeance) = fall (upon)


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’


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


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


Lexical Ambiguity Resolution

to draw a distinction - provodit' razlichie Both verbs are extremely ambiguous:

• draw - more than 50 meanings

• provodit’ - more than 10 meanings


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.


Idiomatic translation: LF Temp

March: in - март: в2 Tuesday: on - вторник: в1 dawn: at - рассвет: на2 moment: at - момент: в1 Easter: at – пасха: на1


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


Sample Dictionary Entry (Excerpt): CHANCE

CHANCE1

POR:S

SYNT:COUNT,PREDTO,PREDTHAT

DES:'FACT','ABSTRACT’


CHANCE

D1.1:OF,'PERSON'

D2.1:OF,'FACT'

D2.2:TO2

D2.3:THAT1


CHANCE

SYN1: OPPORTUNITY

MAGN: GOOD1, FAIR1, EXCELLENT

ANTIMAGN: SLIGHT, SLIM, POOR, LITTLE1, SMALL

OPER1: HAVE, STAND1

REAL1-M: TAKE


CHANCE

ANTIREAL1-M: MISS1

INCEPOPER1: GET

FINOPER1: LOSE

CAUSFUNC1: GIVE <TO1>

ZONE:R

TRANS:ШАНС/СЛУЧАЙ


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’)


CHANCE

N:02CHECK2.1 DOM(X,*,*)DO1 ZAMRUZ:Z(SLUCHAJNO)2 STERUZ:X

TRAF:RA-EXPANS.16LA:THAT1

TRAF:RA-EXPANS.22


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


Internet

UNL Architecture

French People

Hindu PeopleSpanish People

Chinese PeopleFrenchChine

se

Spanish

UNL System

Hindi


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


Two MT architectures: Transfer vs. Interlingua

Source text Target text

Interlingua

Transfer


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


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


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)


прибежатьприлететь приплыть приползтиcome(met>run)come(met>plane)come(met>swim)come(met>crawl)

Formation of new UWs


Formation of new UWs

жениться marry(agt>man)выходить замуж marry(agt>woman)

Documents

ETAP-3: State of the Art, Options, and Prospects of Development Leonid Iomdin Institute for Information Transmission Problems Russian Academy of Sciences