A quantitative analysis of tone sandhi in Standard Mandarin and Nanjing Mandarin based on surface pitch contours and underlying pitch targets

Two statistical modelling methods are first used to quantify the third tone sandhi in Standard Mandarin in which the first falling-rising T3 becomes a rising T2 in the T3+T3 disyllabic context. Growth curve analysis suggests non-neutralization of the surface F0 contours of the sandhi tone and its corresponding citation tone (T2), whereas a quantitative F0 target approximation model reveals neutralization of their underlying pitch targets, congruent with the stable and categorical tone shift properties of tone sandhi processes. The same statistical procedure is successfully extended to examine tone sandhi rules in Nanjing Mandarin. Our analysis leads to a proposal to change tonal values based on the Chao's number system of some Nanjing Mandarin monosyllabic tones. The transformation method from acoustic data to Chao's number applies well to our data and proves superior to those previously described in the literature.