This study investigates the low back vowel merger (lot-thought merger) of African American and European American speakers in Washington DC. The study aims to follow up with the previous investigation by Labov et al. (2006) on low back merger in DC, and investigate whether African American speakers in DC are participating in the merger, one of the majority-led sound changes. The study also examines the difference in low back vowel production between African Americans from a particular quadrant of the city, namely, Southeast (SE), and those from elsewhere in DC. Data are taken from forty sociolinguistic interviews with natives of DC. The vowels were analyzed acoustically, taking F1 and F2 measurements at three different points of a vowel. Both the F1 and the F2 dimensions of the low back vowels and the degree of overlap were examined. The degree of overlap was measured by calculating the Pillai score for each speaker, with duration and following environment taken into account. Results indicate that DC is conservatively participating in the merger, with European American speakers exhibiting higher degrees of overlap than African American speakers. An age effect is also observed, but only among African American speakers who are not from SE. The study further argues that the participation in the mainstream sound change by some African Americans can also be analyzed as convergence to the local white norm, and that this convergence is more likely to be carried out by African American speakers who are not from SE, a section of the city in which the contact between African American speakers and European American speakers is minimal.

中文翻译：

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阈限区域的主流声音变化模式：华盛顿特区的低背合并

这项研究调查了华盛顿特区非裔美国人和欧洲裔美国人的低背元音合并（大量思想合并）。该研究旨在跟进 Labov 等人之前的调查。（2006 年）关于 DC 的低背合并，并调查 DC 中的非裔美国人是否参与合并，这是多数主导的声音变化之一。该研究还检查了来自该城市特定象限（即东南部 (SE)）的非裔美国人与来自华盛顿其他地方的非裔美国人之间的低背元音产生的差异。数据来自对 DC 本地人的 40 次社会语言访谈。对元音进行声学分析，在元音的三个不同点进行 F1 和 F2 测量。检查了下背元音的 F1 和 F2 维度以及重叠程度。重叠程度是通过计算每个说话者的 Pillai 分数来衡量的，同时考虑了持续时间和随后的环境。结果表明，DC 保守地参与了合并，与非裔美国人相比，欧洲裔美国人表现出更高程度的重叠。还观察到年龄效应，但仅限于非东南部的非裔美国人。该研究进一步认为，一些非裔美国人对主流声音变化的参与也可以被分析为与当地白人规范的趋同，并且这种趋同更有可能由非东南部的非裔美国人进行。非裔美国人和欧洲裔美国人之间接触最少的城市部分。