The history of machine translation in a nutshell
It is possible to
trace ideas about mechanizing translation processes
back to the seventeenth century, but realistic possibilities
came only in the 20th century. In the mid 1930s,
a French-Armenian Georges Artsrouni and a Russian
Petr Troyanskii applied for patents for ‘translating
machines’. Of the two, Troyanskii's was the more
significant, proposing not only a method for an
automatic bilingual dictionary, but also a scheme
for coding interlingual grammatical roles (based
on Esperanto) and an outline of how analysis and
synthesis might work. However, Troyanskii’s ideas
were not known about until the end of the 1950s.
Before then, the computer had been born.
§2. The pioneers,
1947-1954
Soon after the first
appearance of ‘electronic calculators’ research
began on using computers as aids for translating
natural languages. The beginning may be dated to
a letter in March 1947 from Warren Weaver of the
Rockefeller Foundation to cyberneticist Norbert
Wiener. Two years later, Weaver wrote a memorandum
(July 1949), putting forward various proposals,
based on the wartime successes in code breaking,
the developments by Claude Shannon in information
theory and speculations about universal principles
underlying natural languages. Within a few years
research on machine translation (MT) had begun at
many US universities, and in 1954 the first public
demonstration of the feasibility of machine translation
was given (a collaboration by IBM and Georgetown
University). Although using a very restricted vocabulary
and grammar it was sufficiently impressive to stimulate
massive funding of MT in the United States and to
inspire the establishment of MT projects throughout
the world.
§3. The decade
of optimism. 1954-1966
The earliest systems
consisted primarily of large bilingual dictionaries
where entries for words of the source language gave
one or more equivalents in the target language,
and some rules for producing the correct word order
in the output. It was soon recognised that specific
dictionary-driven rules for syntactic ordering were
too complex and increasingly ad hoc, and the need
for more systematic methods of syntactic analysis
became evident. A number of projects were inspired
by contemporary developments in linguistics, particularly
in models of formal grammar (generative-transformational,
dependency, and stratificational), and they seemed
to offer the prospect of greatly improved translation.
Optimism remained
at a high level for the first decade of research,
with many predictions of imminent "breakthroughs".
However, disillusion grew as researchers encountered
"semantic barriers" for which they saw
no straightforward solutions. There were some operational
systems – the Mark II system (developed by IBM and
Washington University) installed at the USAF Foreign
Technology Division, and the Georgetown University
system at the US Atomic Energy Authority and at
Euratom in Italy – but the quality of output was
disappointing (although satisfying many recipients’
needs for rapidly produced information). By 1964,
the US government sponsors had become increasingly
concerned at the lack of progress; they set up the
Automatic Language Processing Advisory Committee
(ALPAC), which concluded in a famous 1966 report
that MT was slower, less accurate and twice as expensive
as human translation and that "there is no
immediate or predictable prospect of useful machine
translation." It saw no need for further investment
in MT research; and instead it recommended the development
of machine aids for translators, such as automatic
dictionaries, and the continued support of basic
research in computational linguistics.
§4. The aftermath
of the ALPAC report, 1966-1980
Although widely condemned as biased
and short-sighted, the ALPAC report brought a
virtual end to MT research in the United States
for over a decade and it had great impact elsewhere
in the Soviet Union and in Europe. However, research
did continue in Canada, in France and in Germany.
Within a few years the Systran system was installed
for use by the USAF (1970), and shortly afterwards
by the Commission of the European Communities
for translating its rapidly growing volumes of
documentation (1976). In the same year, another
successful operational system appeared in Canada,
the Meteo system for translating weather reports,
developed at Montreal University.
In the 1960s in the
US and the Soviet Union MT activity had concentrated
on Russian-English and English-Russian translation
of scientific and technical documents for a relatively
small number of potential users, who would accept
the crude unrevised output for the sake of rapid
access to information. From the mid-1970s onwards
the demand for MT came from quite different sources
with different needs and different languages. The
administrative and commercial demands of multilingual
communities and multinational trade stimulated the
demand for translation in Europe, Canada and Japan
beyond the capacity of the traditional translation
services. The demand was now for cost-effective
machine-aided translation systems that could deal
with commercial and technical documentation in the
principal languages of international commerce.
The 1980s witnessed the emergence
of a wide variety of MT system types, and from
a widening number of countries. First there were
a number of mainframe systems, whose use continues
to the present day. Apart from Systran, now operating
in many pairs of languages, there was Logos (German-English
and English-French); the internally developed
systems at the Pan American Health Organization
(Spanish-English and English-Spanish); the Metal
system (German-English); and major systems for
English-Japanese and Japanese-English translation
from Japanese computer companies.
The wide availability of microcomputers
and of text-processing software created a market
for cheaper MT systems, exploited in North America
and Europe by companies such as ALPS, Weidner,
Linguistic Products, and Globalink, and by many
Japanese companies, e.g. Sharp, NEC, Oki, Mitsubishi,
Sanyo. Other microcomputer-based systems appeared
from China, Taiwan, Korea, Eastern Europe, the
Soviet Union, etc.
Throughout the 1980s
research on more advanced methods and techniques
continued. For most of the decade, the dominant
strategy was that of ‘indirect’ translation via
intermediary representations, sometimes interlingual
in nature, involving semantic as well as morphological
and syntactic analysis and sometimes non-linguistic
‘knowledge bases’. The most notable projects of
the period were the GETA-Ariane (Grenoble), SUSY
(Saarbrücken), Mu (Kyoto), DLT (Utrecht), Rosetta
(Eindhoven), the knowledge-based project at Carnegie-Mellon
University (Pittsburgh), and two international multilingual
projects: Eurotra, supported by the European Communities,
and the Japanese CICC project with participants
in China, Indonesia and Thailand.
The end of the decade
was a major turning point. Firstly, a group from
IBM published the results of experiments on a system
(Candide) based purely on statistical methods. Secondly,
certain Japanese groups began to use methods based
on corpora of translation examples, i.e. using the
approach now called ‘example-based’ translation.
In both approaches the distinctive feature was that
no syntactic or semantic rules are used in the analysis
of texts or in the selection of lexical equivalents;
both approaches differed from earlier ‘rule-based’
methods in the exploitation of large text corpora.
A third innovation was the start
of research on speech translation, involving the
integration of speech recognition, speech synthesis,
and translation modules – the latter mixing rule-based
and corpus-based approaches. The major projects
are at ATR (Nara, Japan), the collaborative JANUS
project (ATR, Carnegie-Mellon University and the
University of Karlsruhe), and in Germany the government-funded
Verbmobil project. However, traditional rule-based
projects have continued, e.g. the Catalyst project
at Carnegie-Mellon University, the project at
the University of Maryland, and the ARPA-funded
research (Pangloss) at three US universities.
Another feature of
the early 1990s was the changing focus of MT activity
from ‘pure’ research to practical applications,
to the development of translator workstations for
professional translators, to work on controlled
language and domain-restricted systems, and to the
application of translation components in multilingual
information systems.
These trends have
continued into the later 1990s. In particular, the
use of MT and translation aids (translator workstations)
by large corporations has grown rapidly – a particularly
impressive increase is seen in the area of software
localisation (i.e. the adaptation and translation
of equipment and documentation for new markets).
There has been a huge growth in sales of MT software
for personal computers (primarily for use by non-translators)
and even more significantly, the growing availability
of MT from on-line networked services (e.g. AltaVista,
and many others). The demand has been met not just
by new systems but also by ‘downsized’ and improved
versions of previous mainframe systems. While in
these applications, the need may be for reasonably
good quality translation (particularly if the results
are intended for publication), there has been even
more rapid growth of automatic translation for direct
Internet applications (electronic mail, Web pages,
etc.), where the need is for fast real-time response
with less importance attached to quality. With these
developments, MT software is becoming a mass-market
product, as familiar as word processing and desktop
publishing.
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