Experimental Design - Notes and Technical Information

Formulas: The formulas for computing the different specialized statistics and graphs are provided in the respective contexts, in the Introductory Overview, and the Results dialog boxes (see the Index).
Parameter Estimation: The parameter estimation for 2(k-p) and Plackett-Burman designs, 3(k-p) and Box-Behnken designs, mixed 2 and 3 level full and fractional factorial designs, central composite and response surface designs, and for mixture designs is accomplished via sweeping (e.g., see Dempster, 1969).
Analyzing Replications and Blocked Designs via Categorized Surface Plots: Stats 3D XYZ Graphs contain very powerful tools for analyzing response surfaces and mixtures. In fact, some of those options permit analyses that are usually not discussed in standard texts on this subject. Specifically, you can fit 3D surfaces to your data, categorized by some other variable. For example, if you replicated a standard central composite design 4 times, it may be very informative to see how similar the surfaces are when fitted to each replication. This would give you a graphical indication of the reliability of the results, and where (e.g., in which region of the surface) deviations occur.