Graphic Scaling of Qualitative Terms

This article describes an investigation carried out to determine the perceived intervals between the successive descriptive terms on subjective picture and sound quality category scales. This study involved participants in five geographical areas of the U.S., and also in Rome, Italy (in the Italian language). The intervals were found to be regular, and the meanings of the words were found to vary only slightly with geographic region and culture. It was concluded that these category scales are ordinal, not interval, in nature, and that interval or ratio scales should be used when the “distances” between test stimuli are under examination.