Tone as a Predictor of Mutual Intelligibility of Chinese Dialects

This paper attempts to establish the importance of differences in the tone inventories for the mutual intelligibility of 15 Chinese dialects. Tone influence for mutual intelligibility was tested in two studies. In the first study mutual intelligibility was measured through opinion testing. The fable “The North Wind and the Sun” was read by one male speaker in each of 15 Chinese dialects with melody and was subsequently monotonized. Both versions were presented to groups of 24 listeners for each of the 15 dialects. In this way we obtained intelligibility judgments for all 225 combinations of speaker and listener dialects. The results show that the absence of pitch in the monotonized version only marginally affected the intelligibility judgments. In the second study we determined the mutual intelligibility of the same 15 dialects (again 225 combinations of speaker and listener dialects) using functional intelligibility tests (recognition of words in isolation and in sentences). The intelligibility scores were then correlated with tonal distance measures computed in three different ways on representative word lists for the 15 dialects: (i) Levenshtein string edit distance on 3-digit tone transcriptions, (ii) Levenshtein distance with symbols for starting level and tonal change, and (iii) a perceptually weighted tone distance measure. None of the distance measures correlated with the intelligibility scores, so that our overall conclusion is that differences in lexical tones contribute little to the mutual intelligibility of Chinese dialects.