FrF2.catlg128 (version 1.2-3)

Catalogues: Catalogues of regular 128 run designs of various factor numbers

Description

Catalogues of regular 128 run designs of various factor numbers

Usage

catlg128.8to15
catlg128.16
catlg128.17
catlg128.18
catlg128.19
catlg128.20
catlg128.21
catlg128.22
catlg128.23
catlg128.24
catlg128.25
catlg128.26to33

Author

Ulrike Groemping

Details

The files contain catalogues for regular fractional factorial designs in 128 runs; the numbers after the period indicate the number(s) of factors covered by the respective catalogue. All the catalogues are lists of class catlg. They are provided in support of package FrF2.

Originally, their main intention was to support automatic search of clear designs with options estimable and clear=TRUE in function FrF2. For this purpose, in principle, a complete catalogue of resolution IV designs in 128 runs would be needed. The catalogues come from Xu (2009; supplement on his website up to 25 factors) or Mee (2012, personal communication) and have been enriched by information on clear interactions (entry clear.2fis for each element).

Since version 2 of package FrF2, the catalogues can also support blocking of designs by the method proposed by Godolphin (2020), automated as described in Groemping (2021); with this method, blocking can (but need not) be combined with requiring specific 2fis to be clear. A few catalogue elements that are useful for that method have been added to the catalogue catlg in package FrF2. If a desired blocked design cannot be obtained in adequate quality by using entries from catlg or from the suitable catalogue from this package, one may have to resort to the larger catalogues that are available from the author's website (see also next paragraph).

For the search of clear designs, Wu, Mee and Tang (2012) proved that one need not consider designs with no 5-letter words, as they are always dominated by a better design that can clearly accomodate the same two-factor interactions. Therefore, as of version 1.1 of this package, the resolution IV designs in the catalogues have been reduced to those that do have 5-letter words. For the search for clear designs, it even suffices to search dominating designs only. These are identified by the dominating element of each catalogue entry. The previous complete catalogues of designs can be downloaded from the author's website. Catalogues for 25 to 33 factors have been made available with version 1.2 of the package.

If one of these catalogues is used in the select.catlg option of function FrF2, the function is guaranteed to find the best clear design in 128 runs for the requested number of factors, when used with its option estimable.

For earlier versions of the package, the catalogues had to be loaded with a data() command. This is no longer required, and not even supported; the catalogues will now be automatically loaded on first use.

References

Godolphin, J. (2020). Construction of Blocked Factorial Designs to Estimate Main Effects and Selected Two-Factor Interactions. J. Roy. Statist. Soc. B 83, 5-29. Groemping, U. (2021). An algorithm for blocking regular fractional factorial 2-level designs with clear two-factor interactions. Computational Statistics & Data Analysis 153, 1-18. Mee, R. (2012) Catalogues of even/odd designs produced by Robert Block. Personal communication. Wu, H., Mee, R. and Tang, B. (2012) Fractional Factorial Designs With Admissible Sets of Clear Two-Factor Interactions. Technometrics 54, 191-197. Xu, H. (2009) Algorithmic Construction of Efficient Fractional Factorial Designs With Large Run Sizes. Technometrics 51, 262-277.

See Also

See Also FrF2, catlg

Examples

catlg128.8to15[1:5]

# \donttest{
## example of using a catalogue from this package with function FrF2
## for keeping interactions clear
## the design in the example will also be found with the default catalogue
    ## because arrays for all compromise plans with up to 24 factors 
    ## have been added to catlg with FrF2 version 1.1-1
plan <- FrF2(128, 23, estimable=compromise(23,1:2)$requirement, select.catlg=catlg128.23)
summary(plan)
length(catlg128.23)

## example of using a catalogue from this package with function FrF2
## for blocking a design
requirement <- compromise(13,1)$requirement
## loop through designs from catlg 
nn1 <- names(catlg128.8to15[nruns(catlg128.8to15)==128 & nfac(catlg128.8to15)==13])
for (nam in nn1){
  suppressMessages(
    des128fromcatlg <- try(
         FrF2(design=nam, blocks=32,
            factor.names=Letters[15:27], estimable=requirement, 
            alias.block.2fis = TRUE, select.catlg=catlg128.8to15), 
        silent=TRUE)
    )
  ## stop at first success
  if (!"try-error" %in% class(des128fromcatlg)) break
}
summary(des128fromcatlg)
# }