Longitudinal analysis of English speech produced by Japanese children and automatic evaluation of prosody

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K00789
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 02100:Foreign language education-related
• Research Institution: Doshisha University
• Principal Investigator: Kato Tsuneo 同志社大学, 理工学部, 教授 (60607258)
• Co-Investigator(Kenkyū-buntansha): 菅原 真理子 同志社大学, 文学部, 教授 (10411050) ; 山本 誠一 同志社大学, 研究開発推進機構, 嘱託研究員 (20374100)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 小中学生 / 英語音声 / 追跡的分析 / 無強勢母音 / 韻律評価

Outline of Final Research Achievements

We analyzed English read speech produced by a hundred Japanese junior high school students with various linguistic backgrounds to reveal the effects of linguistic environments in preschool and elementary school on English pronunciation. We compared the quality and quantity of the produced unstressed English vowels among three groups of students: those who received primary education in Japanese at domestic schools, those who received bilingual education in 50% English and 50% Japanese domestically, and those who received primary education in English internationally.
To automatically evaluate accents of English words and stresses of short phrases without referencing a native speaker's speech, we proposed an automatic prosody evaluation method by estimating reference prosody using a Transformer encoder. Experimental results demonstrated significant improvements in subjective-objective score correlations on English word and short phrase utterances produced by Japanese university students.

Free Research Field

音声信号処理

Academic Significance and Societal Importance of the Research Achievements

国内における英語教育ではコミュニケーション能力を育むため早期化が行われたが，小学生以前の言語環境，国内における集中的な英語教育がコミュニケーションの土台である発音に与える影響は明らかではない．本研究は英語教育のさらなる早期化がもたらす効果の予測に資すると考えられる．また，自動韻律評価は将来の英語コミュニケーションの自習を可能にするコンピュータ支援言語学習システムの高度化に資する．