古代の言語を復元する

SOCIETY & CULTURE - Posted by Yasmin Anwar-UC Berkeley on Monday, February 18, 2013 17:35 - 0 Comments (1 VOTES, AVERAGE: 5.00 OUT OF 5)
‘Time machine’ brings back ancestor languages
Not only will the computer program speed up linguists' ability to rebuild the world’s proto-languages on a large scale, boosting our understanding of ancient civilizations based on their vocabularies, but it can also provide clues to how languages might change years from now. (Credit: "moai" via Shutterstock)
UC BERKELEY (US) — A new computer program can rapidly reconstruct “proto-languages”—the linguistic ancestors from which all modern languages have evolved.

へえこんな言語研究もあるのかという記事がありましたのでご紹介します。probabilistic modelを活用して自動的に古代の言語を短時間で復元してくれるコンピュータープログラムを発表した研究があるようです。それによって当時の文化も推測できるのではと語っています。下記のキャプションにまとまっています。

Not only will the computer program speed up linguists' ability to rebuild the world’s proto-languages on a large scale, boosting our understanding of ancient civilizations based on their vocabularies, but it can also provide clues to how languages might change years from now.

研究者の声とともにその方法も説明してくれているのが以下です。85パーセントの精度がいいのか悪いのかよく分かりませんが。。。

“What excites me about this system is that it takes so many of the great ideas that linguists have had about historical reconstruction, and it automates them at a new scale: more data, more words, more languages, but less time,” says Dan Klein, an associate professor of computer science at University of California, Berkeley and co-author of the paper published online in the Proceedings of the National Academy of Sciences.

The research team’s computational model uses probabilistic reasoning—which explores logic and statistics to predict an outcome—to reconstruct more than 600 Proto-Austronesian languages from an existing database of more than 140,000 words, replicating with 85 percent accuracy what linguists had done manually.

While manual reconstruction is a meticulous process that can take years, this system can perform a large-scale reconstruction in a matter of days or even hours, researchers say.

この研究によって過去の言語が復元でき、当時の文化を理解する助けとなるだｋでなく、このモデルを援用すれば、今後言語はどのように変化していくか推測できるようになるのではと語っています。

Not only will this program speed up the ability of linguists to rebuild the world’s proto-languages on a large scale, boosting our understanding of ancient civilizations based on their vocabularies, but it can also provide clues to how languages might change years from now.

“Our statistical model can be used to answer scientific questions about languages over time, not only to make inferences about the past, but also to extrapolate how language might change in the future,” says Tom Griffiths, associate professor of psychology, director of the Computational Cognitive Science Lab, and another co-author of the paper.

僕みたいな素人はやっぱりコンピューターは凄いとなってしまいがちなんですが、この計算モデルの基礎となっているのはthe established linguistic theoryとあります。長年の研究の積み重ねがあったからこの計算モデルができたわけです。コンピューターはその手順を自動化する、スピードアップすることが特徴のようです。

The computational model is based on the established linguistic theory that words evolve along the branches of a family tree—much like a genealogical tree—reflecting linguistic relationships that evolve over time, with the roots and nodes representing proto-languages and the leaves representing modern languages.

Using an algorithm known as the Markov chain Monte Carlo sampler, the program sorted through sets of cognates—words in different languages that share a common sound, history and origin—to calculate the odds of which set is derived from which proto-language. At each step, it stored a hypothesized reconstruction for each cognate and each ancestral language.

TOEIC学習者にもおなじみになったコーパスは同時代の言語の使われ方を見る方法として活用しているものですが、長い時間に言語そのものがどう変化していくかを見ていく方法があるというのも興味深いですね。