An Experimental Analysis of Pitch Patterns in Japanese Speakers of English with Verification by Speech Re-Synthesis

Certain irregularities in utterances of a word or phrase occur in English as spoken by Japanese native subjects (Japanese English, henceforth). This study considers such pitch patterns as one of the most common causes of deficiencies in Japanese English, and that Japanese English would have better pitch patterns if its peculiarities are modified. Firstly, pitch patterns of Japanese English are statistically analyzed. The analytical results provide a rule for modifying the pitch patterns of Japanese English, in order to improve naturalness. To check the appropriateness of the rule, the pitch patterns of several samples of Japanese English are acoustically modified and resynthesized. The modified speeches are evaluated in a listening experiment taken by native English speakers. Averagely, over threefold subjects support the proposed modification against original speeches. Therefore, the results indicate practical verification of modifying ways of Japanese English.