We present a corpus-based investigation of how the pitch contours of monosyllabic words are realized in spontaneous conversational Mandarin, focusing on the effects of words' meanings. We used the generalized additive model to decompose a given observed pitch contour into a set of component pitch contours that are tied to different control variables and semantic predictors. Even when variables such as word duration, gender, speaker identity, tonal context, vowel height, and utterance position are controlled for, the effect of word remains a strong predictor of tonal realization. We present evidence that this effect of word is a semantic effect: word sense is shown to be a better predictor than word, and heterographic homophones are shown to have different pitch contours. The strongest evidence for the importance of semantics is that the pitch contours of individual word tokens can be predicted from their contextualized embeddings with an accuracy that substantially exceeds a permutation baseline. For phonetics, distributional semantics is a new kid on the block. Although our findings challenge standard theories of Mandarin tone, they fit well within the theoretical framework of the Discriminative Lexicon Model.

翻译：本文基于语料库研究了单音节词在自发会话国语中的音高曲线实现方式，重点关注词义的影响。我们采用广义可加模型将观测到的音高曲线分解为与不同控制变量及语义预测因子相关联的组分音高曲线。即使控制了词长、性别、说话者身份、声调语境、元音高度和话语位置等变量，词汇效应仍是声调实现的重要预测因子。我们证明这种词汇效应本质上是语义效应：词义被证明是比词汇本身更优的预测指标，且异形同音词呈现出不同的音高曲线。语义重要性的最有力证据在于，单个词例的音高曲线可通过其语境化嵌入向量进行预测，其准确率显著超越置换基线。对于语音学而言，分布语义学是新兴的研究范式。尽管本研究发现对标准国语声调理论构成挑战，但其与判别式词汇模型的理论框架高度契合。