Eisenberg L S, Dirks D D, Takayanagi S, Martinez A S
UCLA School of Medicine, Division of Head and Neck Surgery, Los Angeles, CA, USA.
J Speech Lang Hear Res. 1998 Apr;41(2):327-39. doi: 10.1044/jslhr.4102.327.
The purpose of this investigation was to determine whether subjective judgments of clarity or intelligibility would be rated equally among conditions in which speech was equated for predicted intelligibility (using the Speech Intelligibility Index, SII) but varied in bandwidth. Twenty listeners with normal hearing rated clarity and intelligibility for sentence material (Hearing In Noise Test) in speech-shaped noise at six paired low- and high-pass filtered conditions in which SII was equated for each pair. For three paired conditions, predicted intelligibility increased as SII increased monotonically (0.3, 0.4, 0.5). In the remaining paired conditions, SII continued to increase monotonically (0.6, 0.7, 0.8) but predicted intelligibility was held at a maximal level (> or = 95%). Predicted intelligibility was estimated from the transfer function relating SII to speech recognition scores determined in preliminary experiments. Differences in ratings between paired low- and high-pass filtered sentences did not reach statistical significance for either clarity or intelligibility, indicating that the spectral differences at equivalent SIIs did not influence the judgments for either of the two dimensions. For conditions in which predicted intelligibility increased, both clarity and intelligibility ratings increased in a similar manner. For conditions in which predicted intelligibility was maximized, intelligibility ratings remained the same statistically across conditions while clarity ratings changed modestly. Although high correlations were observed between clarity and intelligibility ratings, intelligibility ratings were consistently higher than clarity ratings for comparable conditions. The results indicated that listeners with normal hearing produced clarity and intelligibility ratings for the same speech material and experimental conditions that were highly related but differed in magnitude. Caution is required when substituting clarity for intelligibility.
本研究的目的是确定在语音的预测可懂度相等（使用语音可懂度指数，SII）但带宽不同的条件下，清晰度或可懂度的主观判断评分是否相等。20名听力正常的听众对句子材料（噪声中的听力测试）在六种低通和高通滤波配对条件下的清晰度和可懂度进行评分，在这些配对条件中，每对条件的SII相等。对于三对条件，预测可懂度随着SII单调增加（0.3、0.4、0.5）。在其余的配对条件中，SII继续单调增加（0.6、0.7、0.8），但预测可懂度保持在最高水平（≥95%）。预测可懂度是根据在初步实验中确定的将SII与语音识别分数相关联的传递函数估算得出的。低通和高通滤波句子配对之间的评分差异在清晰度或可懂度方面均未达到统计学显著性，这表明在等效SII下的频谱差异不会影响这两个维度中任何一个维度的判断。对于预测可懂度增加的条件，清晰度和可懂度评分均以类似方式增加。对于预测可懂度最大化的条件，不同条件下的可懂度评分在统计学上保持不变，而清晰度评分有适度变化。尽管清晰度和可懂度评分之间观察到高度相关性，但在可比条件下，可懂度评分始终高于清晰度评分。结果表明，听力正常的听众对相同语音材料和实验条件给出的清晰度和可懂度评分高度相关但数值不同。用清晰度替代可懂度时需谨慎。
