This study analyzes representative Mexican folk vocal melodies using MIDI feature extraction, examining ambitus, pitch-class entropy, and interval distribution. It also explores the relationship between these features and song popularity, as measured by Spotify plays. The study employs MATLAB and the MIDI Toolbox for extracting musical features and performing statistical analysis. The findings reveal a significant variation in ambitus, with values ranging from 8 to 27 semitones, indicating a diverse compositional style and vocal demand across the genre. The analysis of pitch-class entropy showcases a broad spectrum of melodic complexity, with Armando Manzanero's `Somos Novios' displaying the highest entropy, suggesting varied and complex melodic structures, while traditional pieces like `La Bamba' exhibit lower entropy, indicating simpler, more repetitive patterns. The interval distribution predominantly features prime intervals (P1), major and minor seconds (M2, m2), pointing to a compositional preference for close, contiguous intervals that contribute to the melodies' accessibility and appeal. Statistical analysis do not establish a significant correlation between the ambitus or entropy and the number of Spotify plays.

翻译：本研究采用MIDI特征提取技术分析具有代表性的墨西哥民间声乐旋律，考察其音域范围、音级熵值及音程分布特征。同时探讨了这些音乐特征与歌曲流行度（以Spotify播放量为衡量指标）之间的关联。研究利用MATLAB及MIDI工具箱进行音乐特征提取与统计分析。结果显示：音域范围存在显著差异（8至27个半音），表明该音乐类型在创作风格与声乐要求上具有多样性；音级熵分析揭示了旋律复杂度的广泛分布，其中Armando Manzanero的《Somos Novios》呈现最高熵值，暗示其多变而复杂的旋律结构，而《La Bamba》等传统作品熵值较低，体现更简单、重复性强的模式特征；音程分布以同度音程（P1）、大二度（M2）和小二度（m2）为主，表明作曲家偏好采用紧密相邻的音程以增强旋律的可接受性与感染力。统计分析未发现音域范围或熵值与Spotify播放量之间存在显著相关性。