| In the design
of experiments the design generators
are the relationships that are used to create
a fractional
factorial design.
In the 24-1 design shown below
we have allocated 'D' to the column
that contains the 'ABC' interaction:
|
|
A
BCD
|
B
ACD |
C
ABD |
AB
CD |
AC
BD |
BC
AD |
D
ABC
|
|
1
|
-1
|
-1
|
-1
|
1
|
1
|
1
|
-1
|
|
2
|
1
|
-1
|
-1
|
-1
|
-1
|
1
|
1
|
|
3
|
-1
|
1
|
-1
|
-1
|
1
|
-1
|
1
|
|
4
|
1
|
1
|
-1
|
1
|
-1
|
-1
|
-1
|
|
5
|
-1
|
-1
|
1
|
1
|
-1
|
-1
|
1
|
|
6
|
1
|
-1
|
1
|
-1
|
1
|
-1
|
-1
|
|
7
|
-1
|
1
|
1
|
-1
|
-1
|
1
|
-1
|
|
8
|
1
|
1
|
1
|
1
|
1
|
1
|
1
|
The design generator for this design is:
D = ABC
Once the design generator has been selected
the defining
relationships (defining words)
and the rest of the aliasing
structure follows.
Note that this is a 24-1 design
and the choice of design generator is obvious.
In a 2n-2 or higher design there
will be several design generators, and several
feasible choices.
|
