Central Composite Response Surface Method

This example validates the calculation of the central composite response surface method in Weibull++.

The data are from Example 11-1 on page 431 in the book Design and Analysis of Experiments by Douglas C. Montgomery, John Wiley & Sons, 2001.

From the book, the ANOVA table is:

The final equation in terms of the actual values of these two factors is:


 * $$\begin{align}

Yield= -1430.52285+7.80749 * time + 13.27053 * temp-0.05505 * time^2 - 0.04005 * temp^2 + 0.01 * time * temp \end{align}$$

The maximum yield is achieved at 80.21 with time = 87 minutes and temperature = 176.5 F.

The software results match the book results. The ANOVA table is:



The final equation in terms of the actual factors is:



The maximum yield is achieved at 80.21, as shown in the optimization plot. The values at the red dash line are the optimal values for factor A and factor B. The blue line corresponds to the maximum Y value.