The overall theme of this special issue is intra-individual variation, that is, the observable variation within individuals’ behaviour, which plays an important role in the humanities area as well as in the social sciences. While various fields have recognised the complexity and dynamism of human thought and behaviour, intra-individual variation has received less attention in regard to language acquisition, use and change. Linguistic research so far lacks both empirical and theoretical work that provides detailed information on the occurrence of intra-individual variation, the reasons for its occurrence and its consequences for language development as well as for language variation and change. The current issue brings together two subdisciplines – psycholinguistics and variationist sociolinguistics – in juxtaposing systematic and non-systematic intra-individual variation, thereby attempting to build a cross-fertilisation relationship between two disciplines that have had surprisingly little connection so far. In so doing, we address critical stock-taking, meaningful theorizing and methodological innovation.

中文翻译：

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简介：调和心理语言学和变异主义社会语言学中个体内部变异的方法

本期专刊的总体主题是个体内部变异，即个体行为内的可观察变异，这在人文领域以及社会科学中都起着重要作用。尽管各个领域已经认识到人类思想和行为的复杂性和动态性，但个人内部变异在语言习得，使用和变更方面的关注较少。迄今为止，语言学研究缺乏经验和理论研究，这些研究没有提供有关个体内部变异的发生，其发生的原因及其对语言发展以及语言变异和变化的影响的详细信息。本期杂志将系统语言和非系统性个体内部并置并列在一起，将心理语言学和变异主义社会语言学这两个子学科整合在一起，从而试图在迄今几乎没有任何联系的两个学科之间建立跨受精关系。通过这样做，我们解决了关键的盘点，有意义的理论和方法论创新。