Table 7.5 summarizes basic design types that you can construct with the FACTEX procedure by providing example code for each type.

Table 7.5: Basic Designs Constructed by the FACTEX Procedure

Design Type |
Example Statements |
---|---|

A full factorial design in three factors, each at two levels coded as –1 and +1. |
proc factex; factors Pressure Temperature Time; examine design; run; |

A full factorial design in three factors, each at three levels coded as –1, 0, and +1. |
proc factex; factors Pressure Temperature Time / nlev= 3; examine design; run; |

A full factorial design in three factors, each at two levels. The entire design is replicated twice, and the design with recoded factor levels is saved in a SAS data set. |
proc factex; factors Pressure Temperature Time; output out= SavedDesign designrep= 2 Pressure cvals=('low' 'high') Temperature nvals=(200 300) Time nvals=(10 20); run; |

A full factorial design in three factors, each at two levels coded as –1 and +1. Each run in the design is replicated three times, and the replicated design is randomized and saved in a SAS data set. |
proc factex; factors Pressure Temperature Time; output out= SavedDesign pointrep= 3 randomize; run; |

A full factorial design in three control factors, each at two levels coded as –1 and +1. A noise factor design ( |
proc factex; factors+ Pressure Temperature Time; output out =+ SavedDesign pointrep=+ OutArray; run; |

A full factorial blocked design in three factors, each at two levels coded as –1 and +1. The design is arranged in two blocks and saved in a SAS data set. By default, the block variable is named BLOCK and the two block levels are numbered 1 and 2. |
proc factex; factors Pressure Temperature Time; blocks nblocks= 2; output out= SavedDesign; run; |

A full factorial blocked design in three factors, each at two levels coded as –1 and +1. Each block contains four runs; the block variable is renamed and the block levels of character type are recoded. The design is saved in a SAS data set. |
proc factex; factors Pressure Temperature Time; blocks size= 4; output out= SavedDesign blockname= Machine cvals=('A' 'B' ); run; |

A fractional factorial design of resolution 4 in four factors, each at two levels coded as –1 and +1. The size of the design is eight runs. |
proc factex; factors Pressure Temperature Time Catalyst; size design= 8; model resolution= 4; examine design; run; |

A one-half fraction of a factorial design in four factors, each at two levels coded as –1 and +1. The design is of maximum resolution. The design points, the alias structure, and the confounding rules are listed. |
proc factex; factors Pressure Temperature Time Catalyst; size fraction= 2; model resolution=maximum; examine design aliasing confounding; run; |

A one-quarter fraction of a factorial design in six factors, each at two levels coded as –1 and +1. Main effects are estimated, and some two-factor interactions are considered nonnegligible. The design is saved in a SAS data set. |
proc factex; factors x1-x6; size fraction= 4; model estimate=( x1 x2 x3 x4 x5 x6 ) nonneg =( x1*x5 x1*x6 x5*x6 ); output out = SavedDesign; run; |