Measuring Expressive Music Performances: a Performance Science Model using Symbolic Approximation

Music Performance Science (MPS), sometimes termed systematic musicology in Northern Europe, is concerned with designing, testing and applying quantitative measurements to music performances. It has applications in art musics, jazz and other genres. It is least concerned with aesthetic judgements or with ontological considerations of artworks that stand alone from their instantiations in performances. Musicians deliver expressive performances by manipulating multiple, simultaneous variables including, but not limited to: tempo, acceleration and deceleration, dynamics, rates of change of dynamic levels, intonation and articulation. There are significant complexities when handling multivariate music datasets of significant scale. A critical issue in analyzing any types of large datasets is the likelihood of detecting meaningless relationships the more dimensions are included. One possible choice is to create algorithms that address both volume and complexity. Another, and the approach chosen here, is to apply techniques that reduce both the dimensionality and numerosity of the music datasets while assuring the statistical significance of results. This dissertation describes a flexible computational model, based on symbolic approximation of timeseries, that can extract time-related characteristics of music performances to generate performance fingerprints (dissimilarities from an ‘average performance’) to be used for comparative purposes. The model is applied to recordings of Arnold Schoenberg’s Phantasy for Violin with Piano Accompaniment, Opus 47 (1949), having initially been validated on Chopin Mazurkas.1 The results are subsequently used to test hypotheses about evolution in performance styles of the Phantasy since its composition. It is hoped that further research will examine other works and types of music in order to improve this model and make it useful to other music researchers. In addition to its benefits for performance analysis, it is suggested that the model has clear applications at least in music fraud detection, Music Information Retrieval (MIR) and in pedagogical applications for music education

A Computational Model of Immanent Accent Salience in Tonal Music

Accents are local musical events that attract the attention of the listener, and can be either immanent (evident from the score) or performed (added by the performer). Immanent accents involve temporal grouping (phrasing), meter, melody, and harmony; performed accents involve changes in timing, dynamics, articulation, and timbre. In the past, grouping, metrical and melodic accents were investigated in the context of expressive music performance. We present a novel computational model of immanent accent salience in tonal music that automatically predicts the positions and saliences of metrical, melodic and harmonic accents. The model extends previous research by improving on preliminary formulations of metrical and melodic accents and introducing a new model for harmonic accents that combines harmonic dissonance and harmonic surprise. In an analysis-by-synthesis approach, model predictions were compared with data from two experiments, respectively involving 239 sonorities and 638 sonorities, and 16 musicians and 5 experts in music theory. Average pair-wise correlations between raters were lower for metrical (0.27) and melodic accents (0.37) than for harmonic accents (0.49). In both experiments, when combining all the raters into a single measure expressing their consensus, correlations between ratings and model predictions ranged from 0.43 to 0.62. When different accent categories of accents were combined together, correlations were higher than for separate categories (r = 0.66). This suggests that raters might use strategies different from individual metrical, melodic or harmonic accent models to mark the musical events

Reconsidering memorisation in the context of non-tonal piano music

Performers, pedagogues and researchers have shared interest in the topic of musical memorisation for centuries. A large and diverse body of studies on this subject has contributed to the current understanding of musicians’ views of performing from memory, as well as the mechanisms governing encoding and retrieval of musical information. Nevertheless, with a few exceptions, existing research is still highly based on tonal music and lacks further examination in the musical world of non-tonality. The convention of performing from memory is a well-established practice for particular instruments and musical genres, but an exception is often made for recent styles of repertoire moving away from tonality. No study to date has systematically investigated the reasons for such exception and musicians’ views on this matter. Moreover, the existing principles of memorisation that are thought to apply to musicians in the highest levels of skill are strongly based on the use of conceptual knowledge of tonal musical vernacular. Such knowledge is often obscured or absent in non-tonal repertoire. This thesis aims to extend the findings of previous research into musical memorisation in the context of non-tonal piano repertoire by documenting pianists’ views and practices in committing this music to memory. An interview study with pianists expert in contemporary music (Chapter 3) establishes the background for the thesis. A variety of views on performing contemporary music from memory were reported, with several pianists advocating benefits from performing this repertoire by heart and others from using the score. Memorisation accounts revealed idiosyncrasy and variety, but emphasised the importance of specific strategies, such as the use of mental rehearsal, principles of chunking applicable to this repertoire and the importance of different types of memory and their combination. The second study (Chapter 4) explores the topic in further depth, by thoroughly examining the author’s entire process of learning and memorising a newly commissioned non-tonal piece for prepared piano. This study extends findings from performance cue (PC) theory. This widely recognised account of expert memory in music suggests that musicians develop retrieval schemes hierarchically organised around their understanding of musical structure, using different types of PCs. The use of retrieval schemes in this context is confirmed by this study. The author organised the scheme around her own understanding of musical structure, which was gradually developed while working through the piece, since the music had no aural model available or ready-made structural framework to hold on to early in the process. Extending previous research, new types of PCs were documented and, for the first time, negative serial position effects were found for basic PCs (e.g., fingering, notes, patterns) in long-term recall. Finally, the study provided behavioural evidence for the use of chunking in non-tonal piano music. The third study (Chapters 5 and 6) extends these findings to a serial piece memorised by six pianists. Following a multiple-case study approach, this study observed in great depth memorisation approaches carried out by two of those pianists, who performed the music very accurately from memory, and by one pianist who performed less accurately. The first two pianists developed retrieval schemes based on their understanding of musical structure and different types of PCs, mainly basic and structural. Comparisons between the pianists revealed very different views of musical structure in the piece. Even so, both musicians used such understanding to organise encoding and retrieval. The pianist with the least accurate performance adopted an unsystematic approach, mainly relying on incidental memorisation. The absence of a conceptual retrieval scheme resulted in an inability to fully recover from a major memory lapse in performance. The findings of this research provide novel insights into pianists’ views towards performing non-tonal music from memory and into the cognitive mechanisms governing the encoding and retrieval of this music, which have practical applications for musicians wishing to memorise non-tonal piano music