Perceiving the relationship between discrete and continuous data: A comparison of sonified data display formats

This study compared the effectiveness of two auditory display designs for conveying the relationship between discrete and continuous data. Participants judged the relationship between simulated data representing “sea temperature, ” (a continuous variable) and “storm occurrence ” (a categorical variable) by rating the strength of covariation between these variables and qualitatively describing the relationship for one of two types of auditory displays. One format integrated the representation of storms and sea temperature into a single pitch-varying “stream” by signaling storms occurrence by momentary amplitude and timbre changes. The other format presented the storm occurrence information as atonal percussive events separate from the pitch-varying stream that represented temperature. While both formats led to statistically equivalent proportions of verbal descriptions of the temperature-storm relationships present in the simulated data samples, the integrated display produced higher correlations between ratings of the strength of the temperature-storm relationship and the actual storm-temperature covariation present within each data sample. [Keywords: Sonification, perception of covariation, auditory graphs, multivariate data display