STRUCTURE IN MUSICAL RHYTHM CAN BE MEASURED
using a number of analytical techniques. While some
techniques—like circular statistics or grammar
induction—rely on strong top-down assumptions,
assumption-free techniques can only provide limited
insights on higher-order rhythmic structure. I suggest
that research in music perception and performance can
benefit from systematically adopting phase space plots,
a visualization technique originally developed in mathematical
physics that overcomes the aforementioned limitations.
By jointly plotting adjacent interonset intervals
(IOI), the motivic rhythmic structure of musical phrases,
if present, is visualized geometrically without making any
a priori assumptions concerning isochrony, beat induction,
or metrical hierarchies. I provide visual examples
and describe how particular features of rhythmic patterns
correspond to geometrical shapes in phase space plots. I
argue that research on music perception and systematic
musicology stands to benefit from this descriptive tool,
particularly in comparative analyses of rhythm production.
Phase space plots can be employed as an initial
assumption-free diagnostic to find higher order structures
(i.e., beyond distributional regularities) before proceeding
to more specific, theory-driven analyses.