World Library  
Flag as Inappropriate
Email this Article

Example-based machine translation

Article Id: WHEBN0036171096
Reproduction Date:

Title: Example-based machine translation  
Author: World Heritage Encyclopedia
Language: English
Subject: Natural language processing, Hybrid machine translation, Rule-based machine translation, Transfer-based machine translation, Timeline of machine translation
Publisher: World Heritage Encyclopedia

Example-based machine translation

Example-based machine translation (EBMT) is a method of machine translation often characterized by its use of a bilingual corpus with parallel texts as its main knowledge base at run-time. It is essentially a translation by analogy and can be viewed as an implementation of a case-based reasoning approach to machine learning.

Translation by analogy

At the foundation of example-based machine translation is the idea of translation by analogy. When applied to the process of human translation, the idea that translation takes place by analogy is a rejection of the idea that people translate sentences by doing deep linguistic analysis. Instead, it is founded on the belief that people translate by first decomposing a sentence into certain phrases, then by translating these phrases, and finally by properly composing these fragments into one long sentence. Phrasal translations are translated by analogy to previous translations. The principle of translation by analogy is encoded to example-based machine translation through the example translations that are used to train such a system.

Other approaches to machine translation, including statistical machine translation, also use bilingual corpora to learn the process of translation.


Example-based machine translation was first suggested by Makoto Nagao in 1984. B.Pevzner suggested the idea (looks like "translation memory") in 1975 year on seminar " Machine translation" in International center of scientific and technological information. (Moscow) [1] Makoto Nagao pointed out that it is especially adapted to translation between two totally different languages, such as English and Japanese. In this case, one sentence can be translated into several well-structured sentences in another language, therefore, it is no use to do the deep linguistic analysis characteristic of rule-based machine translation.


Example of bilingual corpus
English Japanese
How much is that red umbrella? Ano akai kasa wa ikura desu ka.
How much is that small camera? Ano chiisai kamera wa ikura desu ka.

Example-based machine translation systems are trained from bilingual parallel corpora containing sentence pairs like the example shown in the table above. Sentence pairs contain sentences in one language with their translations into another. The particular example shows an example of a minimal pair, meaning that the sentences vary by just one element. These sentences make it simple to learn translations of portions of a sentence. For example, an example-based machine translation system would learn three units of translation from the above example:

  1. How much is that X ? corresponds to Ano X wa ikura desu ka.
  2. red umbrella corresponds to akai kasa
  3. small camera corresponds to chiisai kamera

Composing these units can be used to produce novel translations in the future. For example, if we have been trained using some text containing the sentences:

President Kennedy was shot dead during the parade. and The convict escaped on July 15th. We could translate the sentence The convict was shot dead during the parade. by substituting the appropriate parts of the sentences.

Phrasal verbs

Example-based machine translation is best suited for sub-language phenomena like phrasal verbs. Phrasal verbs have highly context-dependent meanings. They are common in English, where they comprise a verb followed by an adverb and/or a preposition, which are called the particle to the verb. Phrasal verbs produce specialized context-specific meanings that may not be derived from the meaning of the constituents. There is almost always an ambiguity during word-to-word translation from source to the target language.

As an example, consider the phrasal verb "put on" and its Hindi meaning. It may be used in any of the following ways:

  • Ram put on the lights. (Switched on) (Hindi translation: Jalana)
  • Ram put on a cap. (Wear) (Hindi translation: Pahenna)

See also


  1. ^

Further reading

External links

  • Cunei - an open source platform for data-driven machine translation that grew out of research in EBMT, but also includes recent advances from the SMT field
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.