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Generates a 2^k-p fractional factorial design.

Usage

fracDesign(
  k = 3,
  p = 0,
  gen = NULL,
  replicates = 1,
  blocks = 1,
  centerCube = 0,
  random.seed = 1234
)

Arguments

k

Numeric value giving the number of factors. By default k is set to `3`.

p

Numeric integer between `0` and `7`. p is giving the number of additional factors in the response surface design by aliasing effects. A 2^k-p factorial design will be generated and the generators of the standard designs available in fracChoose() will be used. By default p is set to `0`. Any other value will cause the function to omit the argument gen given by the user and replace it by the one out of the table of standard designs (see: fracChoose). Replicates and blocks can be set anyway!

gen

One or more defining relations for a fractional factorial design, for example: `C=AB`. By default gen is set to NULL.

replicates

Numeric value giving the number of replicates per factor combination. By default replicates is set to `1`.

blocks

Numeric value giving the number of blocks. By default blocks is set to `1`.

centerCube

Numeric value giving the number of center points within the 2^k design. By default centerCube is set to `0`.

random.seed

Seed for randomization of the design

Value

The function fracDesign returns an object of class facDesign.c.

Examples

#Example 1
#Returns a 2^4-1 fractional factorial design. Factor D will be aliased with
vp.frac = fracDesign(k = 4, gen = "D=ABC")
#the three-way-interaction ABC (i.e. I = ABCD)
vp.frac$.response(rnorm(2^(4-1)))
# summary of the fractional factorial design
vp.frac$summary()
#> Information about the factors:
#> 
#>            A       B       C       D
#> low       -1      -1      -1      -1
#> high       1       1       1       1
#> name       A       B       C       D
#> unit                                
#> type numeric numeric numeric numeric
#> -----------
#>   StandOrder RunOrder Block  A  B  C  D rnorm.2..4...1..
#> 7          7        1     1 -1  1  1 -1       0.03572991
#> 2          2        2     1  1 -1 -1  1       0.11297506
#> 6          6        3     1  1 -1  1 -1       1.42855203
#> 1          1        4     1 -1 -1 -1 -1       0.98340378
#> 4          4        5     1  1  1 -1 -1      -0.62245679
#> 3          3        6     1 -1  1 -1  1      -0.73153600
#> 8          8        7     1  1  1  1  1      -0.51666972
#> 5          5        8     1 -1 -1  1  1      -1.75073344
#> 
#> ---------
#> 
#> Defining relations:
#> I =  ABCD 		Columns: 1 2 3 4 
#> 
#> Resolution:  IV 
#> 

#Example 2
#Returns a full factorial design with 3 replications per factor combination and 4 center points
vp.rep = fracDesign(k = 3, replicates = 3, centerCube = 4)
#Summary of the replicated fractional factorial design
vp.rep$summary()
#> Information about the factors:
#> 
#>            A       B       C
#> low       -1      -1      -1
#> high       1       1       1
#> name       A       B       C
#> unit                        
#> type numeric numeric numeric
#> -----------
#>    StandOrder RunOrder Block  A  B  C  y
#> 27         27        1     1  0  0  0 NA
#> 13         13        2     1 -1 -1  1 NA
#> 24         24        3     1  1  1  1 NA
#> 12         12        4     1  1  1 -1 NA
#> 5           5        5     1 -1 -1  1 NA
#> 10         10        6     1  1 -1 -1 NA
#> 14         14        7     1  1 -1  1 NA
#> 19         19        8     1 -1  1 -1 NA
#> 8           8        9     1  1  1  1 NA
#> 16         16       10     1  1  1  1 NA
#> 20         20       11     1  1  1 -1 NA
#> 6           6       12     1  1 -1  1 NA
#> 23         23       13     1 -1  1  1 NA
#> 17         17       14     1 -1 -1 -1 NA
#> 7           7       15     1 -1  1  1 NA
#> 2           2       16     1  1 -1 -1 NA
#> 18         18       17     1  1 -1 -1 NA
#> 28         28       18     1  0  0  0 NA
#> 15         15       19     1 -1  1  1 NA
#> 22         22       20     1  1 -1  1 NA
#> 21         21       21     1 -1 -1  1 NA
#> 4           4       22     1  1  1 -1 NA
#> 25         25       23     1  0  0  0 NA
#> 9           9       24     1 -1 -1 -1 NA
#> 26         26       25     1  0  0  0 NA
#> 3           3       26     1 -1  1 -1 NA
#> 11         11       27     1 -1  1 -1 NA
#> 1           1       28     1 -1 -1 -1 NA