Randomization and Experimentation
W. J. Youden · Technometrics · 1972
Randomization, often specified as an indispensable requirement in experimental design, is required only when the order or position of the experimental unit influences the performance of the unit. Randomization, when required, may give an arrangement that is obviously undesirable and one that may doom the particular experimental program. A system of constrained randomization is proposed that eliminates the undesirable arrangements without sacrificing the customary gains achieved by randomization.