Abstract

Improving Multiple Response Optimization with Overlaid and Desirability Contour Plots

Six Sigma practitioners using DOE routinely optimize several responses at once, and often they will stop at the single “optimal” settings reported by the Derringer-Suich desirability function without asking the next question: how robust is that solution?

This webinar focuses on the use of Overlaid Contour Plots and Desirability Contour Plots, that turn multiple response optimization from a single-number answer into a visual exploration of the feasible design space.  We start with Montgomery's chemical process example (two factors, three responses) where the geometry is clean and each plot's role is easy to see, then scale up to the classic Tire Tread Compound example from the original Derringer-Suich paper (three factors, four responses).

Across both examples, attendees will learn how to:

• Read an Overlaid Contour Plot to see the full feasible region where every response stays within its bounds, not just where composite desirability peaks.
• Use Desirability Contour Plots to assess robustness around the optimum, distinguishing flat plateaus from cliffs where small shifts in the X's collapse desirability.

Combine both with the MRO Calculator to choose settings that are both near-optimal and defensible against real-world process variation.

This session assumes familiarity with factorial and response surface DOE. Attendees will leave with a practical, repeatable approach for picking multi-response settings their process can actually hold.

About John

John Noguera is Co-founder and Chief Technology Officer of SigmaXL, Inc., a leading provider of user-friendly Excel add-ins for Lean Six Sigma tools, statistical & graphical analysis, and Monte Carlo simulation. He leads the development of SigmaXL and DiscoverSim with a passion for ease of use, practical & powerful features, and statistical accuracy.  John is a certified Six Sigma master black belt and was an instructor at Motorola University. He has authored conference papers on Statistical Process Control and Six-Sigma Quality and is a contributing author in the Encyclopedia of Statistics in Quality and Reliability (Wiley).