5. Process Improvement
5.4. Analysis of DOE data

5.4.5.

How to interpret DOE results

Final model used to make conclusions and decisions

Assume that you have a final model that has passed all the relevant tests (visual and quantitative) and you are ready to make conclusions and decisions. These should be responses to the questions or outputs dictated by the original experimental goals.

Checklist relating DOE conclusions or outputs to experimental goals or experimental purpose:

A checklist of how to compare DOE results to the experimental goals

• Do the responses differ significantly over the factor levels? (comparative experiment goal)
• Which are the significant effects or terms in the final model? (screening experiment goal)
• What is the model for estimating responses?
• Full factorial case (main effects plus significant interactions)
• Fractional factorial case (main effects plus significant interactions that are not confounded with other possibly real effects)
• RSM case (allowing for quadratic or possibly cubic models, if needed)
• What responses are predicted and how can responses be optimized? (RSM goal)
• Contour plots
• Settings for confirmation runs and prediction intervals for results