Why Proportion of Discriminators is Method-Specific
Rousseau, B., & Ennis, D. M. (2007). IFPress, 10(3), 2-3.
“If we make this change only 10% of our consumers will be able to detect it”, may be a very appealing statement to managers in consumer products companies. These managers are often faced with the need to make product changes and substitutions to change ingredients, lower costs, switch to more stable sources of raw materials, comply with government regulations, or develop more healthful products. Usually there is an attempt to ensure that consumers notice as little difference as possible in the sensory performance of the product. In the food and personal care industries, methodologies used to investigate consumer perception include several discrimination techniques such as the duo-trio method, the triangular method and directional difference tests (such as the 2-Alternative Forced Choice or 2-AFC method.)
Figure 1. Estimation of the proportion of discriminators in the population.