Investigation of operationally more powerful duo-trio test protocols: Effects of different reference schemes

Sensory discrimination by consumers of multiple stimuli from a reference: Stimulus configuration in A-Not AR and constant-ref. duo-trio superior to triangle and unspecified tetrad?

“…This test power or precision of a measure has been theorized based on the precondition of perfect memory and no reduction in the clarity of the sensory information during a subject's sensory and cognitive processes involved in performing the discrimination test (Kim, Kim, Cho, & Lee, 2015). Different from theoretical test power based on predicted variance for a given size of d 0 , operational test power refers to operational capability; that is, the test not being unfavorably interfered with by physiological or cognitive perceptual processes, leading to measure correctly the true sensory differences between stimuli (Kim & Lee, 2012;van Hout et al, 2011). In SDT and Thurstonian modeling, when studying a certain size of sensory difference, a more operationally powerful discrimination test method will result in a larger d 0 with a higher lower confidence limit.…”

“…The most common overall discrimination test methods using consumer subjects previously reported in experimental situations that have one reference and multiple stimulus types include the triangle (Kuesten, 2001), duo-trio (Kim & Lee, 2012), same-different (Kuesten, 2001), A-Not A (Bi & Ennis, 2001;Christensen, Cleaver, & Brockhoff, 2011;Lee, van Hout, & O'Mahony, 2007) and degree of difference (DOD) tests (Aust, Gacula, Beard, & Washam, 1985;Hahn et al, 2012;Michon & McDonnell, 2008). In these previous studies, with the exception of Kuesten (2001), no empirical comparison of the different methods was performed.…”

“…In contrast to this classification method, there are discrimination test designs using a fixed reference: the A-Not A, A-Not A with Reminder (A-Not AR), 2-AFC with Reminder (2-AFCR), and constant-reference duo-trio tests (Kim & Lee, 2012). A-Not AR and 2-AFCR, which use the reminder paradigm, present a fixed reference as a reminder before each test (see Hautus, van Hout, and Lee (2009) for more explanation of the reminder paradigm).…”

“…DTF/2-AFCR test. Here the duo-trio test is denoted by DTF (the traditional version, duo-trio with the reference presented first), indicating the position of the reference in the stimulus presentation (see Rousseau, Stroh, and O'Mahony (2002), Kim, Lee, and Lee (2010), and Kim and Lee (2012) for various versions of duo-trio with the reference in different stimulus positions).…”

“…For d 0 > 0.9, it is apparent that the theoretical test power does not matter under the condition of equalizing the number of stimuli and subjects but does when varying the number of tests. In this situation, operational issues including physiological effects and cognitive factors (Kim & Lee, 2012;Kim et al, 2014;Lee, Chae, & Lee, 2009) that can be largely affected by the stimulus configuration in the replicated tests, may play a major role in determining the applied discrimination performance and the operational test power. In other words, although the theoretical test powers are all equally sufficient, some methods could be more susceptible to operational hindrances such as sensory adaptation and memory degradation and thus result in lower discrimination performance than the other methods in application/operation.…”