Shrivastav Rahul
Department of Communication Sciences and Disorders, University of Florida, Gainesville, Florida 32611, USA.
J Voice. 2006 Jun;20(2):211-22. doi: 10.1016/j.jvoice.2005.04.005. Epub 2005 Sep 13.
Experiments on disordered voice quality with multidimensional scaling (MDS) have resulted in solutions with low R-square and have failed to show consistent dimensions across different listeners. These findings have been suggested to indicate large individual differences in the perception of voice quality. However, these inconsistencies may originate from several factors, including random stimulus selection, instructions that encourage listeners to respond to global difference in pairs of voices, and noisy perceptual data. This experiment used MDS techniques to study individual differences in perception of breathiness. The voices in the experiment were selected to have a relatively wide variation in breathiness but only minimal variation in roughness, strain, and fundamental frequency. Additionally, listeners were instructed specifically to rate similarities in breathiness rather than judging global differences in voices, and several judgments from each listener were averaged to minimize noise in the data. It was hypothesized that these modifications would result in an MDS solution that accounted for greater variance in perceptual data than previously shown. Results show that averaging multiple responses from each listener increased the R-square from 45% to approximately 75%. The poor R-square and large individual differences in voice quality perception observed in past research may have partly resulted from the experimental procedures in previous studies. These findings suggest that individual differences in the perception of voice quality are not as large as previously thought, and a model of voice quality perception for an "average" listener may be a good representation for the general population.
运用多维标度法（MDS）对嗓音质量紊乱进行的实验得出了决定系数较低的结果，并且未能在不同听众中呈现出一致的维度。这些研究结果表明，在嗓音质量的感知方面存在很大的个体差异。然而，这些不一致可能源于几个因素，包括随机的刺激选择、鼓励听众对成对嗓音的整体差异做出反应的指导语，以及有噪声的感知数据。本实验使用MDS技术来研究呼吸声感知方面的个体差异。实验中的嗓音被选择为在呼吸声方面有相对较大的变化，但在粗糙度、紧张度和基频方面只有极小的变化。此外，专门指导听众对呼吸声的相似性进行评分，而不是判断嗓音的整体差异，并且对每个听众的多个判断进行平均，以最小化数据中的噪声。据推测，这些改进将产生一个能解释感知数据中比之前所显示的更大方差的MDS解决方案。结果表明，对每个听众的多个反应进行平均，使决定系数从45%提高到了约75%。过去研究中观察到的决定系数较低以及嗓音质量感知方面的巨大个体差异，可能部分是由先前研究中的实验程序导致的。这些发现表明，嗓音质量感知方面的个体差异并不像之前认为的那么大，并且一个“普通”听众的嗓音质量感知模型可能对一般人群有很好的代表性。
