You use the FACTORS statement to start the construction of a new design by naming the factors in the design. The FACTORS statement
clears all previous specifications for the design (number of runs, block size, and so on). Use it when you want to start a
new design.
Note: The FACTORS statement should be the first statement following the PROC FACTEX statement.
In the FACTORS statement,
-
factor-names
-
lists names for the factors in the design. These names must be valid SAS variable names. See the section Types of Factors for details.
The following option is available:
-
NLEV=q
-
specifies the number of levels for each factor in the design. The value of q must be an integer greater than or equal to 2. The default value for q is 2. In order to construct a design that involves either fractionation or blocking, q must be either a prime number or an integer power of a prime number. For the reason behind this restriction, see the section
Structure of General Factorial Designs.