Psychophysics involves the response of an organism to changes in the environment perceived by
the five senses [Stevens 1960]. Some examples include how the human body perceives sound
loudness, lighting brightness, or odor strength.
These psychophysical phenomena lead to sensory responses, which follow a “power law.”
Apparent odor strength grows as a power function of the stimulus odor.
S. S. Stevens showed that this power law (Steven’s Law) follows the equation