Continuous versus Summative Evaluations of Musical Intensity: A Comparison of Two Methods for Measuring Overall Effect

Abstract

The primary purpose of the present study was to compare two different methods of measuring subjects' perceptions of overall effect: (1) a record of subjects' ongoing evaluation that is averaged to obtain an overall rating (labeled “continuous') and (2) a single rating of intensity given by subjects at the conclusion of a music excerpt (labeled ”summative“). Subjects were asked to evaluate the level of musical intensity expressed in various music excerpts. We used the term musical intensity as it is commonly understood, that is, to describe an affective perception of music that conveys strong, ardent, or concentrated emotion. Our use of the term does not refer to its physical/acoustical definition. The results illustrate the nonequivalence of subjects' perceptions of overall intensity and mathematical summaries of their perceptions of intensity as recorded while listening. The two different measurement methods evidence extremely high levels of internal consistency; however, in both between- and within-subject comparisons, the summative responses were higher than the continuous response means. It seems reasonable to conclude that subjects' expressions of overall effect are quite consistent between subjects and between replications, but that arithmetic means of subject responses are not equivalent to subjects' ”psychological averages' (i.e., their post hoc perceptions of overall effect), especially with regard to stimuli whose intensity levels change over the course of a given stimulus example.