N.B.: power tables have been published using the proportion of discriminators in the population. However, as a general rule, the same–different test is slightly more powerful than the triangle and duo–trio tests but less powerful than the 2- and 3-AFC tests, while the power of the A/Not A test is closer to that of the 2-AFC test. A power value would need to be calculated for each criterion location and size. The same–different and A/Not A tests cannot be included in this table because of the issue of response bias. These variations in sample size indicate the larger power of the protocols using the skimming strategy. ![]() In order to reach the same confidence level for the duo–trio, 3-AFC, and triangle tests, we need a sample size of 3092, 64, and 2742 respectively. If we do not detect a significant difference at the 5% level, we are 80% sure that the d' was less than 0.5. For the 2-AFC, first line: if we run 78 tests and detect a significant difference at the 5% level, we are 95% sure that a difference exists between the products.
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