ABSTRACT
Psychophysics is the science of the relationship between energy and the sensations it produces. In the consumer products industry, psychophysics is referred to as sensory evaluation. This chapter describes and discusses ways in which the so-called absolute and differential sensitivity can be quantified. The problem of determining thresholds is therefore a problem of handling variability among and within human observers after the data is collected. A practical consequence of this variability is that thresholds must be considered only as approximate: they will be found to vary somewhat from one determination to another. While the main point of interest may be determining a threshold, several other useful pieces of information can be extracted from information collected for that purpose. In fact, the same procedures used to determine a threshold may be used when some of this other information is the major point of interest.
