This paper is equal parts methodological recommendation and an empirical investigation of the time dimensions of linguistic change. It is increasingly common in the sociolinguistic literature for researchers to utilize speech data that was collected over the course of many decades. These kinds of datasets contain three different time dimensions that researchers can utilize to investigate language change: (i) the speakers’ dates of birth, (ii) the speakers’ ages at the time of the recording, and (iii) the date of the recording. Proper investigation of all three time dimensions is crucial for a theoretical understanding of the dynamics of language change. I recommend utilizing two-dimensional tensor product smooths, fit over speakers’ date of birth and the year of the recording, to analyze the contribution of these three time dimensions to linguistic changes. I apply this method to five language changes, based on data drawn from the Philadelphia Neighborhood Corpus. I find relatively weak evidence for lifespan effects in these changes, robust generational effects, and in one case, evidence of a zeitgeist effect.

中文翻译：

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世代、寿命和时代精神

本文是对语言变化时间维度的等量方法推荐和实证研究。在社会语言学文献中，研究人员利用数十年来收集的语音数据越来越普遍。这些类型的数据集包含三个不同的时间维度，研究人员可以利用它们来调查语言变化：（i）说话者的出生日期，（ii）说话者在录音时的年龄，以及（iii）记录。对所有三个时间维度的适当研究对于从理论上理解语言变化的动态至关重要。我建议使用二维张量积平滑，适合扬声器的出生日期和录音年份，分析这三个时间维度对语言变化的贡献。根据从费城邻里语料库中提取的数据，我将这种方法应用于五种语言变化。我在这些变化中发现了相对较弱的寿命效应证据、强大的代际效应，在一个案例中，还发现了时代精神效应的证据。