can be dropped from the model. Performing the ANOVA using factors A, C, and D, and the interaction terms A:C and A:D, gives the result shown in the following table, in which all the terms are significant (p-value < 0.05). See also Combinatorial design Design of experiments Orthogonal array Plackett–Burman design Taguchi methods Welch's t-test Notes References External links Introduction to Factorial Experimental Designs (The Methodology Center, Penn State University) Factorial Designs (California State University, Fresno) GOV.UK Factorial randomised controlled trials (Public Health England) Design of experiments Statistical process control