Linguistic complexity is neither easily defined nor measured. The challenge in finding reliable ways to measure linguistic complexity is even more pronounced when the variation of contexts in which complexity is measured is taken into account. This paper therefore aims at finding measures for assessing syntactic and lexical complexity that are sensitive and non-overlapping even in a less frequently studied context: spontaneous speech of L1 attriters and highly proficient L2 English speakers. To evaluate operationalizations of syntactic and lexical complexity, several previously proposed measures are applied to a corpus of spontaneous speech and a principal component analysis is conducted. The results show which of the measures group together as underlying variables of syntactic and lexical complexity and how this can inform future operationalizations of complexity.

中文翻译：

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测量长期讲英语的 L2 和讲德语的 L1 的长期使用者的语言复杂性

语言复杂性既不容易定义也不容易测量。当考虑到测量复杂性的上下文的变化时，寻找测量语言复杂性的可靠方法的挑战更加明显。因此，本文旨在寻找评估句法和词汇复杂性的措施，即使在研究较少的上下文中也是敏感且不重叠的：L1 学习者的自发讲话和非常熟练的 L2 英语使用者。为了评估句法和词汇复杂性的操作性，将一些先前提出的措施应用于自发语音语料库，并进行主成分分析。