Diphthongs have a dynamic formant structure. Nevertheless, many quantitative studies of diphthongs are based on measurements at only two points, somewhere in the nucleus and somewhere in the glide. The question arises as to whether analyses based on values at only two points provide an adequate understanding of the dynamics of diphthongs. Wieling (2018) mentions the analysis of /aɪ/ raising in Chicago English in Hualde, Luchkina & Eager (2017) as one of several examples of recent studies where potentially interesting patterns may have been missed because of limited sampling of formant values, and proposes using Generalized Additive Mixed Models (GAMM) to allow a more complete understanding of diphthong dynamics. In this paper, we examine the acoustic nature of the (quasi-)phonemic differentiation between two originally allophonic variants of the diphthong /aɪ/ in the US English of Chicago and the surrounding area. We offer an acoustic analysis based on full formant trajectories of diphthongs with data obtained from a group of 53 speakers. The results of a GAMM analysis are then compared with those obtained in Hualde et al. (2017), which considered values at only two points and from a smaller set of speakers (17). We also discuss the main advantages of GAMM analysis over other techniques that have being proposed for the analysis of differences in vowel formant dynamics.

双元音具有动态共振峰结构。然而，许多双元音的定量研究仅基于两个点的测量，即核中某处和滑行中某处。问题在于仅基于两个点的值的分析是否可以充分理解双元音的动态。Wieling (2018) 在 Hualde, Luchkina & Eager (2017) 中提到芝加哥英语中 /aɪ/ raise 的分析是近期研究的几个例子之一，由于共振峰值的采样有限，可能遗漏了潜在有趣的模式，并提出使用广义加法混合模型 (GAMM) 可以更全面地了解双元音动力学。在本文中，我们检查了芝加哥和周边地区美国英语中双元音 /aɪ/ 的两个原始同位异音变体之间（准）音位差异的声学性质。我们提供基于双元音完整共振峰轨迹的声学分析，数据来自一组 53 位说话者。然后将 GAMM 分析的结果与 Hualde 等人获得的结果进行比较。（2017 年），它只考虑了两点的价值，并且来自一小部分发言者（17）。我们还讨论了 GAMM 分析相对于其他用于分析元音共振峰动态差异的技术的主要优势。然后将 GAMM 分析的结果与 Hualde 等人获得的结果进行比较。（2017 年），它只考虑了两点的价值，并且来自一小部分发言者（17）。我们还讨论了 GAMM 分析相对于其他用于分析元音共振峰动态差异的技术的主要优势。然后将 GAMM 分析的结果与 Hualde 等人获得的结果进行比较。（2017 年），它只考虑了两点的价值，并且来自一小部分发言者（17）。我们还讨论了 GAMM 分析相对于其他用于分析元音共振峰动态差异的技术的主要优势。