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Three Replications with Four Factors
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Suppose you want to determine if the order in which four drugs are given affects the response of a subject. If you have only three subjects to test, you can use the following statements to design the experiment.
proc plan seed=27371;
factors Replicate=3 ordered Drug=4;
run;
These statements produce a design with three replicates of the four levels of the factor Drug arranged in random order. The three levels of Replicate are arranged in order, as shown in Figure 65.1.
Figure 65.1
Three Replications and Four Factors
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You might also want to apply one of four different treatments to each cell of this plan (for example, applying different amounts of each drug). The following additional statements create the output shown in Figure 65.2:
factors Replicate=3 ordered Drug=4;
treatments Treatment=4;
run;
Figure 65.2
Using the TREATMENTS Statement
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© 2009 by SAS Institute Inc., Cary, NC, USA. All
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