Weber's Law: Just Noticeable Difference: Differential Threshold

The differential threshold
The minimal difference that can be detected between two similar stimuli is called the differential threshold, or the just noticeable difference (the j.n.d.). A nineteenth-century German scientist named Ernst Weber discovered that the j.n.d. between two stimuli was not an absolute amount, but an amount relative to the intensity of the first stimulus. Weber’s law, as it has come to be known, states that the stronger the initial stimulus, the greater the additional intensity needed for the second stimulus to be perceived as different. For example, if the price of a half gallon container of premium squeezed orange juice is $5.50, most consumers will probably not notice an increase in 25 cents, and it may take an increase of 50 cents or more before a differencial in price would be noticed. However, a 50 cent increase in the price of gasoline would be noticed very quickly by consumers because it is a significant percentage of the initial cost of gasoline.

According to Weber’s law, an additional level of stimulus equivalent to the j.n.d. must be added for the majority of people to perceive a difference between the resulting stimulus and the initial stimulus. Read the articles listed below in the order that they appear for more information.

This is from the book "Consumer Behavior." It's by Leon G. Schiffman and Leslie Lazar Kanuk. If you want to really know in depth information about consumer behavior, get the book.

Articles Related to Above Topic. Read in Order.

Definition of Perception. Relevance to Marketers and Advertisers

Element of Perception: Sensation: Response to Stimuli

Absolute Threshold of Sensation: Adaption to Advertising: Getting Used To Something

Sensory Adaption: Changing Advertising Campaigns To Reduce

Weber's Law: Just Noticeable Difference: Differential Threshold

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