Elliott L L, Clifton L A, Servi D G
Audiology. 1983;22(3):229-40. doi: 10.3109/00206098309072787.
Previous work demonstrated that adults achieved higher performance scores than young children on a 4-alternative forced-choice (4 AFC), picture-pointing speech identification task even though all stimuli (words and pictures) had been developed to be familiar to 3-year-old inner-city children. It was hypothesized that these results reflected 'word frequency effects' in the sense that, even though children knew the words, adults had much greater experience with the stimuli and, consequently, required less acoustic information for correct performance. In the current study, this hypothesis of word frequency effects was tested by creating new materials in which the stimulus items (recorded words and pictures) remained the same but new picture foils representing less frequently occurring words replaced the incorrect response alternatives. According to Broadbent's word frequency, response bias views, it was hypothesized that adults would show improved performance on the modified test materials, compared to the original ones. Data supported this hypothesis and also showed that, in children, the magnitude of word frequency effects is related to receptive vocabulary skills. This phenomenon needs to be considered in developing clinical tests of speech or language that have a closed-set format.
先前的研究表明，在一项4选1的强制选择（4AFC）图片指向言语识别任务中，成年人的表现得分高于幼儿，尽管所有刺激（单词和图片）都是为城市中心区3岁儿童所熟悉的内容设计的。据推测，这些结果反映了“词频效应”，即尽管儿童认识这些单词，但成年人对这些刺激有更丰富的经验，因此，正确完成任务所需的声学信息更少。在当前的研究中，通过创建新材料来检验这种词频效应的假设，在新材料中，刺激项目（录制的单词和图片）保持不变，但代表低频出现单词的新图片陪衬物取代了错误的反应选项。根据布罗德本特的词频、反应偏差观点，推测与原始测试材料相比，成年人在修改后的测试材料上表现会有所提高。数据支持了这一假设，并且还表明，在儿童中，词频效应的大小与接受性词汇技能有关。在开发具有封闭式格式的言语或语言临床测试时，需要考虑这一现象。
