A Statistical Model for Melody Reduction

TL;DR

This paper introduces a statistical model for melody reduction in classical music, focusing on predicting chord tones using music theory rules and melodic features, aiding musicological analysis and potentially improving automatic chord estimation.

Contribution

It presents a novel probabilistic approach for melodic reduction based on music theory, emphasizing chord tone prediction in classical music and integrating with visualization tools.

Findings

Model effectively predicts chord tones using metric position, duration, and melodic intervals.

Focuses on melodic reduction rather than harmony prediction.

Provides a tool for musicologists to identify non-chord tones and analyze melodies.

Abstract

A commonly-cited reason for the poor performance of automatic chord estimation (ACE) systems within music information retrieval (MIR) is that non-chord tones (i.e., notes outside the supporting harmony) contribute to error during the labeling process. Despite the prevalence of machine learning approaches in MIR, there are cases where alternative approaches provide a simpler alternative while allowing for insights into musicological practices. In this project, we present a statistical model for predicting chord tones based on music theory rules. Our model is currently focused on predicting chord tones in classical music, since composition in this style is highly constrained, theoretically making the placement of chord tones highly predictable. Indeed, music theorists have labeling systems for every variety of non-chord tone, primarily classified by the note's metric position and intervals of approach and departure. Using metric position, duration, and melodic intervals as predictors, we build a statistical model for predicting chord tones using the TAVERN dataset. While our probabilistic approach is similar to other efforts in the domain of automatic harmonic analysis, our focus is on melodic reduction rather than predicting harmony. However, we hope to pursue applications for ACE in the future. Finally, we implement our melody reduction model using an existing symbolic visualization tool, to assist with melody reduction and non-chord tone identification for computational musicology researchers and music theorists.