The LATTICE Procedure

Input Data Set

Four numeric SAS variables, Group, Block, Treatment, and Rep, are used in the input data set to define the lattice design. The Group, Block, and Treatment variables are required in the data set to which PROC LATTICE is applied. For compatibility with previous releases, the third variable can alternatively be named Treatmnt. The Rep variable must be present when the design involves repetition of the entire basic plan.

Group: specifies which orthogonal replication in the basic plan includes the experimental unit. Values of Group must be $1, 2, \ldots , n$ , where n is the number of replicates in the basic plan.
Block: specifies the block in which the experimental unit is present. Values of Block must be $1, 2, \ldots , m$ , where m is the number of blocks in a replication.
Treatment: specifies which treatment was applied to the experimental unit. Values of Treatment must be $1, 2, \ldots , i$ , where i is the number of treatments in a replication.
Rep: specifies which repetition of the basic plan includes the experimental unit. Values of Rep must be $1, 2, \ldots , p$ , where p is the number of replications of the entire basic plan. Thus, the experiment has a total of $np$ replicates.