Predicting vowel inventories: The dispersion‐focalization theory revisited
Predicting vowel inventories: The dispersion‐focalization theory revisited
复制标题
预测元音库存：重新审视色散聚焦理论
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
R. Becker
中科院分区：
文献类型：
--
作者：
R. Becker
色散聚焦理论（DFT）的修正[Schwartz等人，J. Phonetics 25，233-253（1997）]。与DFT一样，当前的计算模型纳入了3.5-Bark谱积分的重心效应（COG），但它与DFT存在偏差，因为COG对元音感知共振峰的实际值和可靠性权重有贡献。COG被重新解释为朝向共振峰合并的加速域：相距小于3.5巴克的共振峰的感知以非线性但连续的方式相互扰动，并且它们的权重增加，但是感知合并和权重最大化仅在声学距离约为2巴克时发生。与其他基于离散度的模型一样，库存主要根据最小离散的元音对进行评估，其中离散度被测量为元音坐标（前两个感知共振峰）之间的加权欧几里得距离。然而，在目前的模型中，权重是以一种原则性很强的方式动态确定的。该模型改进了现有的模型在预测某些普遍的特点，如一系列的前圆元音在大元音库存，作为紧急的财产的库存分散评价函数的某些局部最大值，而不牺牲预测足够的较小的库存。
A revision of the dispersion‐focalization theory (DFT) [Schwartz et al., J. Phonetics 25, 233–253 (1997)] is presented. Like DFT, the current computational model incorporates the center of gravity effect (COG) of 3.5‐Bark spectral integration, but it deviates from DFT in that the COG contributes to the actual values and reliability weights of the perceived formants of vowels. The COG is reinterpreted as a domain of acceleration towards formant merger: the percepts of formants less than 3.5 Barks apart are perturbed towards one another in a nonlinear yet continuous fashion and their weights are increased, but perceptual merger and weight maximization occur only when the acoustic distance is about 2 Bark. Like other dispersion‐based models, inventories are evaluated predominantly according to the least dispersed vowel pair, where dispersion is measured as the weighted Euclidean distance between the vowels coordinates (the first two perceived formants). Yet in the current model the weights are determined dynamically, in a well‐principled manner. This model improves existing models in predicting certain universal traits, such as series of front rounded vowels in large vowel inventories, as emergent properties of certain local maxima of the inventory dispersion evaluation function, without sacrificing predictive adequacy for smaller inventories.