Sample size calculator for sensory discrimination tests in Excel
This tutorial shows how to compute the optimal sample size for your sensory discrimination test in Excel using XLSTAT.
Data to compute the sample size
In this tutorial, we want to perform a triangle discrimination test to determine if a difference is perceived between two cookies. For reasons of time and cost, we want to limit the number of respondents while ensuring that we are in good statistical conditions. Thus, we will look for the number of respondents necessary to obtain a power of the test equal to 0.9.
Setting up the sample calculator for a sensory discrimination test with XLSTAT
Select the menu XLSTAT/Advanced features/Sensory data analysis/Power- Sensory discrimination tests or if you have the sensory focus XLSTAT/ XLSTAT-Sensory / Discrimination tests/Power- Sensory discrimination test. The dialog box appears.
In the General tab, we enter the analysis parameters: 0.05 for the first type error, 0.9 for the power, and d-prime=0 .
Interpret the results of the XLSTAT sample calculator for a sensory discrimination test
In order to obtain results with a power of 0.9, it will be necessary to summon a certain number of respondents, depending on the minimum proportion of correct answers. For our test, we expect to obtain at least 50% of correct answers, which according to the table and graph below indicates that 53 respondents are needed.
For more details on sensory discrimination tests, please refer to the Designs for sensory discrimination tests as well as the Sensory discrimination tests.
Was this article useful?