Question

Acme Snacks wants to make its chips saltier, but it doesn't want to spend more than it has to on salt. A sample of consumers are asked to compare its current chip (saltiness = 100) with saltier versions and to indicate whether the new version is saltier. On average, sample consumers reliably say the new chip is saltier when its saltiness value is 108, but not when its saltiness value is below 108. Assuming Acme Snacks' sample consumers are representative of people in general, which of the following best represents the JND for saltiness?

A) 8
B) 100
C) 108
D) 10
E) 98

Answer 1

The just-noticeable difference (JND) for saltiness in the Acme Snacks scenario is 8, as consumers could reliably detect the chips as saltier at a saltiness value of 108 compared to the original 100.

Step-by-step explanation:

The just-noticeable difference (JND) refers to the smallest change in a sensory stimulus that can be detected. In the context of Acme Snacks and their saltiness levels, the JND represents the smallest increase in saltiness that a consumer can reliably perceive as being saltier than the original chip. Based on the scenario provided, sample consumers could reliably detect an increase in saltiness when the saltiness value rose from 100 to 108 but not below 108. Therefore, the JND for saltiness in this case would be the difference between these two values.

The best representation of the JND for saltiness is 8, which is the increase needed for consumers to reliably perceive the chips as saltier, according to Weber's Law and the information provided in the study. At a saltiness level below 108, consumers could not discern an increase in saltiness reliably; hence, this value reflects the threshold of sensory perception for an increase in saltiness.