Language acquisition is a well-established avenue for language change (Labov, 2007). Given the theoretical importance of language acquisition to language change, it is all the more important to formulate clear theories of transmission-based change. In this paper, we provide a simulation method designed to test the plausibility of different possible transmission-based changes, using the Tolerance Principle (Yang, 2016) to determine precise points at which different possible changes may become plausible for children acquiring language. We apply this method to a case study of a complex change currently in progress: the allophonic restructuring of /æ/ in Philadelphia English. Using this model, we are able to evaluate several competing explanations of the ongoing change and determine that the allophonic restructuring of /æ/ in Philadelphia English is mostly likely the result of children acquiring language from mixed dialect input, consisting of approximately 40% input from speakers with a nasal /æ/ split. We show that applying our simulation to a phonological change allows us to make precise quantitative predications about the progress of this change. Moreover, it forces us to reassess intuitively plausible hypotheses about language change, such as grammatical simplification, in a quantitative and independently motivated framework of acquisition.

中文翻译：

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使用容差原则预测语音变化

语言习得是一种行之有效的语言改变途径（Labov，2007）。鉴于语言习得对语言变化的理论重要性，制定清晰的基于传播的变化理论就显得尤为重要。在本文中，我们提供了一种模拟方法，旨在测试不同可能的基于传输的变化的合理性，使用容忍原则（Yang，2016）来确定不同可能变化可能对儿童获得语言的合理性的精确点。我们将此方法应用于当前正在进行的复杂变化的案例研究：费城英语中 /æ/ 的同位异音重组。使用这个模型，我们能够评估对正在进行的变化的几种相互竞争的解释，并确定费城英语中 /æ/ 的同位异音重组很可能是儿童从混合方言输入中获得语言的结果，其中大约 40% 的输入来自带有鼻音的说话者/æ/ 分裂。我们表明，将我们的模拟应用于语音变化使我们能够对这种变化的进展做出精确的定量预测。此外，它迫使我们在定量和独立动机的习得框架中重新评估关于语言变化的直觉合理假设，例如语法简化。我们表明，将我们的模拟应用于语音变化使我们能够对这种变化的进展做出精确的定量预测。此外，它迫使我们在定量和独立动机的习得框架中重新评估关于语言变化的直觉合理假设，例如语法简化。我们表明，将我们的模拟应用于语音变化使我们能够对这种变化的进展做出精确的定量预测。此外，它迫使我们在定量和独立动机的习得框架中重新评估关于语言变化的直觉合理假设，例如语法简化。