A Brief Overview of MachineTranslation in Europe and North
AmericaPROFILEJohn Hutchins

W. John Hutchins is the author of articles and books on linguistics, information retrieval, and in particular machine translation many available from his website (http://www.hutchinsweb.me.uk).
He is active in the European Association for Machine Translation(president 1995-2004) and the International Association for
Machine Translation (president, 1999-2001).

Abstract: The aim of using computers for translation is not to emulate or rival human translation but to produce roughtranslations which can serve as drafts for published translations, as means for accessing foreign-language information, andas cross-language communication aids. The field of machine translation (MT) covers the usage, research and developmentof computer aids and systems, ranging from production systems for large corporations to Internet aids for individuals. It isa major area of research in both Europe and North America.
Keywords: Machine translation, Europe, America

ties and for the ‘control’ of text input (e.g. use of regular-Types of MT systems

ized language). On the other hand, the quality of MT output is often found to be adequate for less demanding

MT systems are widely available in Europe and Northuses, e.g. for individual ‘occasional’ translation, for identi-

America in three basic versions: ‘corporate’ or ‘enterprise’

fying the main content of foreign texts or for non-technicalversions for large companies; ‘professional’ versions forcommunication between languages.

independent professional translators; and ‘home’ or ‘personal’ systems for occasional users, e.g. for translating

MT software is available from a large number of European

Web pages and emails. The ‘home’ systems are the mostand North American vendors and covering virtually all

basic type, consisting of little more than the core transla-

European language pairs. Here we can mention only thetion engine. The corporate systems include many addi-

most notable (for a full listing see the Compendium oftional aids, for pre- and post-editing of texts, for terminolo-translation software at http://www.hutchinsweb.me.uk/gy management, for project control, etc.

Compendium.htm).

The ‘professional’ systems provide a selection of those

Nearly all cover the major European languages (English,facilities found to be most suitable for translators.

French, German, Italian, Spanish), and many of them alsotranslate from less common Languages (Greek, Polish,Although there have been improvements since MT began

Russian, Hungarian, Turkish, etc.) and from and into

in the 1950s, it is true to say that translation quality is still

Arabic, Chinese, Japanese, Korean, etc. In addition, there

not good enough for publication without revision; Humanare many systems specifically designed for particular lan-intervention or interaction is necessary for publication-guage pairs: English-German (Personal Translator PT),

quality translation.

English-Italian (PeTra), English-Finnish (TranSmart),

Hence, in many environments, the need for editing facili-

Hungarian-English (Morphologic), Arabic-English (Al-252

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Mutarjim Al-Arabey, Al-Nakil, Al-Wafi); French- German

mation has to be updated regularly, and software such as(FB-Active), German-Russian (PROMT), Russian-IBM Websphere has been developed specifically for

Ukrainian (PARS), Portuguese-Spanish and other lan-translating webpages as and when required.

guages (Falatudo), Catalan-Spanish (interNOSTRUM),
etc.

Automatic translation of electronic mail has been relatively
neglected. Most PC based MT software is designed forthis usage, but it is clear that more specialised software isMT for special purposes

desirable. To meet this need, the Translution company ismarketing customized software for translation of compa-

Apart from commercial systems there continue to be cus-

ny-internal email communication.

tom-built systems for company-internal use or for corporate clients. In the United States, the PAHO (PanIn contrast to the situation in Japan and other Asian coun-

American Health Organization) developed onsite systems

tries, the application of MT to patents has been relativelyfor English and Spanish in the early 1980s, followed later

neglected. There are only three systems specifically forby English-Portuguese; the Smart Corporation continues

translating patents: the PaTrans and SpaTrans systems

to develop customized systems for most European lan-developed for LingTech A/S to translate English patents

guages for large corporate clients; and European

into Danish; and the APTrans system designed for gener-

providers of custom-built systems include ESTeam spe-

ating multilingual patent claims from controlled English

cializing in controlled-language systems.

language input.

Many large translation services and multinational companies use MT systems for translating large volumes ofMT and the Internet

texts, e.g. in the United States government institutions(DARPA, USAF, etc.) and large corporations (Xerox,The Internet has produced a rapidly growing demand for

Ford, General Motors, etc.). Major users in Europe arereal-time on-line translation. The need is for fast acquisi-

companies such as SAP and Siemens, and in particulartion of foreign-language information; and top quality out-

the European Commission.

put is not at all essential. Many MT systems are marketed
for the translation of Web pages and of electronic mail,One of the most distinctive features of the European

and there is great and increasing usage of MT services

scene are translation companies providing localisation of(many free), such as the well-known ‘Babelfish’ on

documentation and products - these companies have

AltaVista. and now also available on Yahoo. Others

acquired considerable experience in the use of translation

include FreeTranslation, Google Translator, Tarjim,aids and MT systems. Related to this activity is the devel-WorldLingo, and many more online services are being

opment of software for the localisation of websites. Withadded (see the Compendium of translation software),the growth of the Internet, many companies offer informa-

both for specific language pairs and for the ‘major’ lan-tion about their products and services, which increasingly

guages (English, French, German, Spanish, Arabic,

needs to be made available in other languages. The infor-Japanese, Korean, Chinese).

A Brief Overview of Machine Translation in Europe and North America

Japio 2008 YEAR BOOK 253

began offering its own internally-developed SMT system

MT researchfor Arabic, Chinese, Japanese and Korean into English.
using the resources of Google’ s massive text databases.

Until the mid 1990s, most MT research was still based on

One of the advantages of the SMT approach is that sys-

the implementation of lexical and grammar rules (withtems can be developed quickly - significantly quicker thantranslation via an interlingua or at least ‘deep structure’

RBMT systems. There are many examples in the MT liter-representations) in what is now called rule-based machine

ature of recent years (see the Machine Translationtranslation (RBMT).

Archive.) One example is the statistics-based SpaTrans

Currently, the dominant paradigms of MT research aresystem which has been developed for English-Danishcorpus-based. In statistical machine translation (SMT),

translation of patents by LingTech A/S in Denmark. It haswords and ‘phrases’ (sequences of two or three words)

been evaluated in comparison with the rule-based

from a bilingual corpus (of original texts and their transla-PaTrans system developed in the 1990s from the Eurotrations) are aligned as the basis for a ‘translation model’ ofmodel. On the whole the output quality of the SMT system

word-word (and phrasephrase) frequencies. Translationcompares well with the rule-based system - relatively sim-

involves the selection of the most probable words in theple adjustments can be envisaged to improve treatment oftarget language for each input word and the determination

word order and noun-verb agreement. However, a majorof the most probable sequence of the selected words (onproblem is the occurrence of new terminology, resulting in

the basis of a monolingual ‘language model’).

many ‘unknown’ words in the output. It is, of course, a

Example-based machine translation (EBMT) involves sim-problem for all MT systems. In the case of SMT, there areilar alignment of bilingual data, but here the translation

two possible solutions: the addition of a bilingual diction-

units are larger than individual words or short word

ary database, or the addition of more domain-specificsequences; input sentences are matched against phrases

texts to the bilingual corpus. The latter is generally pre-or clauses (examples) in the corpus, then equivalentferred as it causes less disruption to the core statisticalphrases in the target language are extracted, and adaptedmodel.

and combined in acceptable output sentences. Bothmethods make substantial use of large bilingual corpora,

Probably the most significant development in MT research

but where SMT is based exclusively on statistical correla-in Europe is the establishment of the Euromatrix projecttions, EBMT applies both statistical techniques and lin-(based at Edinburgh University). Its aim is the develop-

guisticsbased methods similar to those of earlier RBMT

ment of open-source MT technologies applicable to all

approaches.

language pairs within Europe, based on hybrid designs

Although SMT research now dominates MT research, thecombining statistical and rule-based methods. There will

great majority of commercial systems are RBMT systems.

be a particular emphasis on languages of new member

Few SMT systems have reached public operational sta-states of the European Union, and on systems for trans-tus. The leader has been Language Weaver offering

lating technical, social and legal documentation.

translation systems for Arabic, Chinese, French, German,
Persian, Romanian, Spanish, etc. to and from English.

The most innovative area of current research is automatic

Most recently, the online ‘Google Translate’ service hastranslation of spoken language. The main centres are254

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ATR in Japan, the Carnegie-Mellon University (USA), theProfessional translators, translation agencies and smaller

University of Karlsruhe (Germany), all collaborating in acompanies prefer computer-based translation tools, andproject (C-STAR consortium) to develop speaker-inde-in particular translator workstations, often referred to bypendent realtime telephone translation systems fortheir most distinctive component as ‘translation memory’

Japanese, English and German. initially for hotel reserva-systems . many developed initially by European compa-tion and conference registration transactions. Until recent-nies. The most widely used currently are: SDL, Transit,ly, there was also in Germany the government-funded

Deja Vu, MultiTrans, LogiTerm, Wordfast, andVerbmobil project to develop a portable aid for business

ProMemoria. Each offer similar ranges of facilities andnegotiations (German, Japanese, English). Speech trans-functions: multilingual split-screen word processing; termi-lation attracts much publicity, but few observers expect

nology recognition, retrieval and management; creation

dramatic developments in the near future. While we canand use of translation memories (bilingual text corpora ofenvisage MT of speech in highly constrained domains

previous translations and their originals); and support for(e.g. telephone enquiries, banking transactions, computer

all European and many Asian languages, both as sourceinput) it seems unlikely that automatic speech translationand target languages. Finally, and not least, workstations

will extend to openended interpersonal communication.

provide access to fully automatic translation if and whenrequired.

The accession of states in Central and Eastern Europe tothe European Union has stimulated research on MT andSignificant ‘by-products’ of the corpus-based MT researchtranslation tools for languages such as Czech, Polish,

have been further development of aids for translators, not

Hungarian, Slovenian, Estonian and Bulgarian. Mention

just improvements in translation memories, their creation

should also be made of research on systems for ‘minority’and exploitation, but also systems for error detection andlanguages in Europe, such as Basque, Catalan andcorrection and for automatic text prediction, i.e. sugges-

Galician in Spain and immigrant languages such as Hindi,tions for text completion to aid human translators who fre-Bengali and Gujarati in the United Kingdom.

quently translate similar technical documents.

MT and human translators

MT in the future

Machine translation is demonstrably cost-effective for

For the translation of texts where the quality of output islarge scale and/or rapid translation of (boring) technicalnot important, machine translation is often the only solu-documentation, (highly repetitive) software localizationtion. For example, it will be uneconomic to produce

manuals, and many other situations where the costs ofhuman translations of scientific and technical documents

MT plus essential human preparation and revision, or thejust for general background information and/or specificcosts of using computerized translation tools (worksta-data. In these cases, MT will increasingly be the onlytions, etc.), are significantly less than those of traditional

answer. And there are new applications where human

human translation with no computer aids.

translation has never featured: the production of draft versions for authors writing in a foreign language; the real-A Brief Overview of Machine Translation in Europe and North America

Japio 2008 YEAR BOOK 255

time translation of television subtitles; the translation of

欧州と北米における機械翻訳概観

information from databases; the on-line translation of Web
pages; the translation of electronic mail; etc.

【概要】
The Internet will drive changes in the nature and application of MT. What users of Internet services are seeking is
information, in whatever language it may have been written or stored. translation is just a means to that end.
Users will want seamless integration of information
retrieval, extraction and summarization systems with automatic translation. There is now active research in crosslingual information retrieval, multilingual summarization,multilingual text generation from databases, and so forth.

MTシステムの型
・欧米の機械翻訳システムは3つの基本形に分類できる：基幹業務向け、職業翻訳家向け、個人向け
・1950年代から改良が継続されたが、率直に言って訳質に関しては手を加えないとそのまま出版できるレベ
ルではない。出版レベルにするには、人手介入が必須となっている。そのために入力では編集機能や制限言語が必要である。MT出力は程々の要求に対しては問題ないレベルになっている。
・欧米では、多くのMT販売業者が存在している。言語

Existing systems have been developed for wellwritten scientific and technical documents and assume human postediting. Internet usage demands systems specifically forthe kind of colloquial (often ill formed and badly spelled)
messages found in emails and chat rooms. The old linguistics rule-based (RBMT) approaches are probably notequal to the task on their own, and we may expect corpus-based methods making use of the voluminous data
available on the Internet itself as the basis of future systems for this application.

対は全ての欧州言語をカバーしている。一覧は、
http://www.hutchinsweb.me.uk/Compendium.
htm に掲載している。
・主要欧州言語は全てカバー：英語、仏語、独語、伊語、西語・共通性の低い言語もサポートしているものが多い：ギリシャ語、ポーランド語、ハンガリー語、トルコ語等々
・＋

アジア言語と双方向翻訳：アラビア語、中国語、日本語、韓国語
・特定言語対に特化したものも多くある：英独、英伊、
英芬、洪英、亜英、仏独、独露、露ウクライナ、葡西、カタール語西Principal works: Machine Translation: Past, Present,Future (Chichester: Ellis Horwood, 1986); An Introduction
to Machine Translation [with Harold Somers] (London:Academic Press, 1992); Editor of MT News International(1991-1997); Compiler of Compendium of Translation
Software (now on his website) (2000 to the present) andof the Machine Translation Archive (http://www.mtarchive.info) (2004 to the present); Editor of Early years in
Machine Translation: Memoirs and Biographies ofPioneers (Amsterdam: John Benjamins, 2000).

特殊用途MT・特定の企業限定にカスタマイズしたもの
米国パンアメリカンヘルス機構の英西（1980年代開発）、最近は英葡スマートコーポレーションの大企業顧客向け多くの欧州言語のカスタマイズシステム
欧州のプロバイダーではESTeamを含む制限言語システム
・大規模多言語ドキュメントを扱う企業
米国政府（DARPA、USAF等）、Xerox、Ford、GeneralMotors等

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欧州 SAP、シーメンス、欧州連合

ATR、米国のCMU、ドイツのカールスルーエ大学が・欧州の特徴
出版物のローカリゼーション

5 機械翻訳技術の向上センターを作っている。
この一部としてWebのローカリーションが含まれる。

・音声翻訳は大衆の興味を惹きつけるが、電話問合せ、銀行取引、コンピュータ入力のような場合を除けば、・電子メールの翻訳は、無視されてきたが、この市場に特化した企業が現れた。

オープンな環境での普及には懐疑的な意見が多い。
・中欧、東欧からEUへの新規加入国の言語や方言も対・特許翻訳システムは3つしかない。これは日本やアジ象になっている。

ア諸国と異なる傾向である。
MTと人手翻訳
MTとインターネット

・MTは、大量で迅速、リアルタイムの技術文書の翻訳

・インターネットはオンラインリアルタイム翻訳の要求をもたらした。に適している。特に繰り返しの多いソフトウェアマニュアルのローカラリゼーションに適している。

・AltaVistaのBabelFish、Yahoo、Google、Free
Translation、Tarjim、WorldLingo等

・人手翻訳に比較して、コンピュータ利用の翻訳は大幅なコストダウンになる。

・追加分は、http://www.hutchinsweb.me.uk/Compendium.htm参照

・職業翻訳家、翻訳会社、小規模翻訳会社は、翻訳メモリシステムを利用している。現在、よく利用されてい・対象言語は、主流の言語対(英、仏、独、西、アラビ
ア語、日、韓、中)、非主流の言語対るのは、SDL、Transit、Déjá Vu、MultiTrans、LogoTerm、Wordfast、ProMemoriaである。
・コーパスベースMTの特徴的な副次効果は、翻訳メモMT研究

リの改良だけでなく、テキスト校正支援や自動テキス

・90年代半ばまで、ルールベースMT（RBMT）が研ト予測への利用である。

究の中心であったが、現在主流の研究パラダイムは、対訳コーパスを用いたコーパスベースMTである。
・統計ベースMT（SMT）は、単語対(あるいは連続した数単語列対)の確率による翻訳モデル

将来のMT
・翻訳品質にこだわらない場面ではMTは必需品である。
特に科学技術文献の翻訳では人手翻訳は経済的ではな

・用例ベースMT（EBMT）は翻訳単位がSMTに比較しい。最近現れたものとしては、外国語で著述する人のて大きく、句や節が対象になる。また、一部、ルール草稿原稿、テレビのサブタイトル、データベース情報、的手法も採用する。

webページ、電子メールの各翻訳である。

・SMTが研究の主流だが、商品化は大半がRBMTである。

・インターネットがMTの性格を変革している。インタ・Language WeaverはSMTのリーダ格であったが、ーネットユーザが求めるのは情報であり、表現される

最近、Googleが独自開発したSMTサービスを始めた。

言語に関係しない。多言語翻訳によるクロス言語検索、・欧州における最も重要な開発は、エディンバラ大学を情報抽出、要約とMTの結合が活発に研究されている。

ベースとするEuromatrixプロジェクトである。その・既存のMTシステムは、正確に記述された文書を対象

特徴はオープンソースによる全欧州言語対のMT開発、に開発されてきたが、インターネットに見られる話し統計ベースとルールベースのハイブリッド方式でる。

言葉の翻訳は非文が多く、RBMTには適さない。イ

技術文献、社会文献、法律文献を扱う。

ンターネット自身のデータを大量に利用するコーパス

・音声翻訳はイノベーティブな研究である。日本のベースMTが中心であると予想している。

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