Machine Translation Level 2

1
Machine Translation (Level 2)

• Anna Sågvall Hein
• GSLT Course, January 2003

2
Translation

• substitute the text material of one language
  (SL) by the equivalent text material of another
  language (TL) (Catford 1965 20)
• Translation consists in producing in the target
  language the closest natural equivalent of the
  text material of the source language, in the
  first hand concerning meaning, in the second hand
  concerning style (Nida 1975 32)
• Translation is in theory impossible, but in
  practice fairly possible Mounin 1967)
• Catford, J. C. (1965), A Linguistic Theory of
  Translation, Oxford Press, England.
• Mounin, G. (1967) Les problèmes théotitiques de
  la traduction. Paris
• Nida, E. (1975), A Framework for the Analysis and
  Evaluation of Theories of Translation, in
  Brislin, R. W. (ed) (1975), Translation
  Application and Research, Gardner Press, New
  York.

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Equivalence

• form
• meaning
• style
• effect

4
Formal and dynamic equivalence

• Formal equivalence focuses attention on the
  message itself, in both form and content. It aims
  to  allow the reader to understand as much of the
  SL context as possible.
• Dynamic equivalence is based on the principle of
  equivalent effect, i.e. that the relationship
  between receiver and message should aim at being
  the same as that between the original receivers
  and the SL message.
• (Nida 75)

5
Can computers translate?

• Not a simple yes or no it depends on the purpose
  of the translation and the required quality.

6
Classical problems with MT

• unrealistic expectations
• bad translations
• difficulties in integrating MT in the work flow
• the Ericsson case

7
Feasibility of machine translation

• Quality in relation to purpose
• Sublanguage
• Spell checked and grammar checked SL
• Controlled language
• Human machine interaction
• Re-use of translations
• Evalution data

8
Translation related tasks

• translation
• browsing
• gisting
• drafting
• message dissemination
• cross-language information searches
• cross-language interchanges

9
MT as a cross-language communication tool

• MT is used not only for pure translation purposes
  but also for writing in a foreign language and
  for browsing (Hutchins 2001)
• Hutchins, J., 2001, Towards a new vision for MT,
  Introductory speech at MT Summit VIII conference,
  18-22 September 2001
• (http//ourworld.compuserve.com/homepages/WJHutchi
  ns/MTS-2001.htm)

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What is MT proper?

• To be considered as MT, a system should provide
• mininally correct morphology
• minimal syntactic processing
• minimal semantic processing
• handle and produce full sentences
• Hutchins, J., 2000, The IAMT Certification
  initiative and defining translation system
  categories (http//ourworld.compuserve.com/homepag
  es/WJHutchins/IAMTcert.htm)

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Sublanguage

• domain
• text type

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Spell checking and grammar checking

• If there are spelling errors or typos in the SL
  dictionary search will fail
• If there are grammatical errors in the SL
  grammatical analysis will fail
• Where and how should spell and grammar checking
  be accounted for? Before or in the process?

13
Controlled language

• controlled vocabulary
• full lexical coverage, e.g. Scania Swedish
• controlled grammar
• full grammatical coverage
• language checker
• e.g. Scania Checker

14
Human intervention

• before
• language checking
• during
• e.g. ambiguity resolution
• after
• post-editing

15
Re-use of translations

• translation memories
• translation dictionaries incl. terminologies
• statistical machine translation
• example-based translation

16
Evaluation of MT

• coverage (recall)
• quality (precision)

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Why machine translation?

• cheaper
• faster
• more consequent

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Examples of MT products

• Systran (http//babelfish.altavista.com/)
• Metal
• Power Translator Pro (LH)
• Lantmark
• Comprendium
• ESTeam
• See further http//ourworld.compuserve.com/homepa
  ges/WJHutchins/Compendium-4.pdf ,
  http//www.foreignword.com/Technology/mt/mt.htm

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Basic strategies

• direct translation
• rule-based translation
• transfer
• lexicalistic approach
• interlingua
• example-based translation
• statistical translation
• hybrids