Split-Plot Designs: What, Why, and How
نویسندگان
چکیده
T HIS provocative remark has been attributed to the famous industrial statistician, Cuthbert Daniel, by Box et al. (2005) in their well-known text on the design of experiments. Split-Plot experiments were invented by Fisher (1925) and their importance in industrial experimentation has been long recognized (Yates (1936)). It is also well known that many industrial experiments are fielded as split-plot experiments and yet erroneously analyzed as if they were completely randomized designs. This is frequently the case when hard-to-change factors exist and economic constraints preclude the use of complete randomization. Recent work, most notably by Lucas and his coworkers (Anbari and Lucas (1994), Ganju and Lucas (1997, 1999, 2005), Ju and Lucas (2002), Webb et al. (2004)) has demonstrated that many experi-
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