Hi @SaraA,
When using the "Fit Definitive Screening", the analysis of Definitive Screening Designs is done in 2 steps to take into account the specific structure of DSD:
- First stage involves main effects identification with the responses values,
- Second stage involves 2-factors interactions and quadratic effects identification (based on Effects Heredity principle) with the responses residuals from the first stage model.
To learn more about the analysis method of DSDs available in the "Fit Definitive Screening Design", I can recommend some ressources and presentations :
I hope these ressources will help you understand the logic behind this analysis method and model fitting.
Victor GUILLER
L'Oréal Data & Analytics
"It is not unusual for a well-designed experiment to analyze itself" (Box, Hunter and Hunter)