Measures of Temporal Pattern Complexity

Abstract

In this study, three measures of temporal pattern complexity were compared with regard to their perceptual validity. The first measure, based on the work of Tanguiane (1993), uses the idea that a temporal pattern can be described in terms of (elaborations of) more simple patterns, which occur simultaneously at different levels. The second measure is based on the complexity measure for finite sequences proposed by Lempel and Ziv (1976), which is related to the number of steps in a self-delimiting production process by which such a sequence is presumed to be generated. The third measure, newly developed here, is rooted in the theoretical framework of rhythm perception of Povel and Essens (1985). It takes into account the ease of coding a temporal pattern and the complexity of the segments resulting from this coding. The perceptual validity of the three measures was evaluated in an experiment in which subjects judged the complexity of 35 temporal patterns. Correlations between the three measures and the collected complexity judgments indicated that the third measure is a much better predictor of temporal pattern complexity than the other two measures. This is probably due to the fact that this measure, unlike the other two, is based on an empirically tested model of rhythm perception that takes into account the isochronous frame against which the rhythm is perceived. Reasons for the differences in performance between the three measures are discussed.