Problems with duration models: Evidence from Chinese

Abstract

Durations of (1) closure, (2) frication noise, (3) aspiration, and (4) voice in Chinese sounds under different linguistic conditions were measured on oscillomink displays of waveforms. A set of rules of percentage duration variation were formulated to reflect the effects of each of several linguistic factors such as distinctive features, syllable structures, word lengths, tone and stress patterns, etc. The notion of “incompressibility” [I. Lehiste, J. Acoust. Soc. Am. 51, 2018–2024 (1972); D. H. Klatt, J. Acoust. Soc. Am. 54, 1102–1104 (1973)], i.e., that durations resist being shortened under combined shortening rules, is discussed. Like English, Chinese vowel durations are incompressible under several shortening rules; unlike English, Chinese consonant durations do not show clear incompressibility. Two problems were found in applying the formula Dj = K*(Di − Dmin) + Dmin [D. H. Klatt, J. Acoust. Soc. Am. 59, 1208–1221 (1976)] in Chinese, one is that Chinese data show two values of “minimum duration” (one duration symptomatic of word length effects, and a shorter duration under neutral tone); another problem is that different combinations of shortening rules may result in different powers of incompressibility in duration.