ABSTRACT
This chapter deals with the practical aspects of directly measuring sensation. Measurement is the assignment of numbers to objects or events according to rules. In the case, the events of interest are sensations or, more exactly, sensation intensities. J. C. Stevens proposed a classification system for measurement scales which has become generally accepted as a useful system for ordering scale properties. Interval scales provide information on the magnitude of perceived differences among samples being scaled as well as on their rank ordering. Because of this additional information, interval scales are more useful than ordinal scales. The overwhelming majority of sensory data in chemometrics is collected by asking observers to taste or smell a sample product and rate the perceived intensities of various attributes on some sort of rating scale. Category rating means the assigning of a number from a fixed and finite range of numbers to represent the intensity of a given sensation.
