Hickey T
Linguistics Institute of Ireland, Dublin.
J Child Lang. 1991 Oct;18(3):553-69. doi: 10.1017/s0305000900011247.
One of the most widely used indices of language development is a measure of utterance length in morphemes (MLUm). This study examines the applicability of MLUm to the acquisition of Irish. MLUm was calculated for data from Cian, aged 1; 11-3; 0. Even when an attempt was made to 'assume the maximum' by counting all possible morphemes, the correlation between a morpheme MLU (MLUm) and a word count MLU (MLUw) was very high (0.99). This points to MLUw being as effective a measure of Irish development as MLUm, as well as being easier to apply and more reliable. MLUw was calculated for the two younger children in the study (Eibhlís 1; 4-2; 1 and Eoin 1; 10-2; 6). An examination of the relationship between the three children's MLUw values and their grammatical complexity as measured on ILARSP (the Irish adaptation of LARSP) indicates that MLUw is a useful preliminary index for early development in Irish. However, further data are necessary to check whether MLUw loses its predictive relationship with grammatical complexity after a certain point. The study emphasizes the caution necessary in applying MLU to languages whose acquisition has not hitherto been studied, and underlines the role of MLU as a preliminary measure, which must not be overinterpreted.
语言发展中使用最广泛的指标之一是语素平均长度（MLUm）。本研究考察了语素平均长度在爱尔兰语习得中的适用性。对1岁11个月至3岁的Cian的数据计算了语素平均长度。即使尝试通过计算所有可能的语素来“取最大值”，语素平均长度（MLUm）与单词计数平均长度（MLUw）之间的相关性也非常高（0.99）。这表明单词计数平均长度（MLUw）在衡量爱尔兰语发展方面与语素平均长度（MLUm）同样有效，而且更易于应用且更可靠。对研究中的两个年幼儿童（Eibhlís，1岁4个月至2岁1个月；Eoin，1岁10个月至2岁6个月）计算了单词计数平均长度（MLUw）。考察三个孩子的单词计数平均长度（MLUw）值与通过ILARSP（LARSP的爱尔兰语改编版）测量的语法复杂性之间的关系表明，单词计数平均长度（MLUw）是爱尔兰语早期发展的一个有用的初步指标。然而，需要更多数据来检验单词计数平均长度（MLUw）在达到某一点后是否会失去与语法复杂性的预测关系。该研究强调在将平均长度应用于此前未研究过习得情况的语言时必须谨慎，并强调平均长度作为一种初步测量方法的作用，绝不能过度解读。
