The split plot with repeated randomised complete block design can reduce psychological biases in consumer acceptance testing
Document Type
Article
Publication Date
4-1-2014
Abstract
A randomised complete block design (RCBD) has been extensively used in consumer testing; however, it is ineffective in preventing sample presentation biases. This study demonstrated a more efficient experimental design [i.e. split plot with repeated randomised complete block design (SPRRCBD)] to help minimise positional and first serving-order (FSO) biases in consumer tests. Results suggested that positional biases were strongly pronounced for the poor-quality sample. Comparing between RCBD and RCBD without FSO experiments, there were significant differences in overall liking (OL) scores of the same sample served at the same position. Hence, omitting the first sample score from data analysis was not recommended. The mean-squared error (MSE) of SPRRCBD was lower than RCBD and RCBD without FSO (2.28, 2.72 and 2.60, respectively), indicating a more powerful design to explain variations in mean hedonic differences. SPRRCBD extracted more explained variances, resulting in a decreased Type-II error in the model. © 2013 Institute of Food Science and Technology.
Publication Source (Journal or Book title)
International Journal of Food Science and Technology
First Page
1106
Last Page
1111
Recommended Citation
Jirangrat, W., Wang, J., Sriwattana, S., No, H., & Prinyawiwatkul, W. (2014). The split plot with repeated randomised complete block design can reduce psychological biases in consumer acceptance testing. International Journal of Food Science and Technology, 49 (4), 1106-1111. https://doi.org/10.1111/ijfs.12406