Tone recognition in Mandarin using focus

Native speakers of Mandarin produce and perceive tones in ways that depend on the focus with which each word is pro- duced (1). This paper gives one approach to improving tone recognition algorithms using focus, by training different sup- port vector machines on syllables conditional on their position with respect to the focused word in a sentence. In a four-way tone classification task on focus-labelled laboratory Mand arin speech data collected by Xu (2), error rates improve from 15.2% without using focus to 8.7% when using focus. Using the fact that tones on syllables in focused words are especially easy to recognize, we propose a tone recognition algorithm that makes use of focus without requiring focus labels in either traini ng or test set. The algorithm has an error rate of 9.8% on this data set.