Typically the Lack of Fit and Pure Error values are included in ANOVA results during using the Design Expert Software. But, some times they are not included in the ANOVA results. Is it because of the type of experimental design (for example full factorial, composite rotatable design, ...)? Or can it be due to the number of input parameters?
Thanks.
At the first stage it is not problem related to statistics. First hand is ordinary practical knowledge and this seems to be difficult enough! In research, statistics can be a good support./ Toni (Docent/associate professor) at the Royal Institute of Technology in Stockholm. [email protected]
You need to have multiple extra degrees of freedom to get the LOF test. You need to remove terms from the model or add extra design points.
You need to replicate points 4+ times to get a Pure error test. This can be done either by replicating the center point 5+ times or replicating design points 4+ times.
- Badges
- Science method
- Similar topics
- Mathematics
- Statistics
- Statistical Modeling
- Analyses of Variance
- ANOVA