Hi!
thanks for your response!
>unfortunately, fractional factorial designs typically require all factors
to
have the same number of levels. Hence, your 2x3x3x5x2 example is not a
simple
special case of a fractional factorial design.
>There are some special plans for mixed level designs, but t
> Yes, you're right. For, say, a 3 x 5 design, one can do this in as few as
7
runs -- but only in general by some version of one-factor-at-a-time (OFAT)
designs, which are inefficient. It is easy, via, say model.matrix() to
write a general function to produce these. But I think it's a bad idea; mo
>If an orthogonal main effect plan exists for the number of trials you
specify, optFederov() in AlgDesign will more than likely find it for
you, since such a design should be an optimal design.
thanks very much to you and the others!!
I have written a little function, and now the syntax to obtai
sorry, some small mistakes in the previuos syntax. This works!
design.test <- gen.orthogonal.design(c(2,4,3),numCards=16)
design.test
gen.orthogonal.design <- function(listFactors,numCards){
library(AlgDesign)
FactorsNames<-c("A","B","C","D","E","F","G","H","J","K","L")
nu
ED] On Behalf Of
> [EMAIL PROTECTED]
> Sent: Monday, January 23, 2006 12:20 PM
> To: Berton Gunter; [EMAIL PROTECTED];
> r-help@stat.math.ethz.ch
> Subject: [R] R: fractional factorial design in R
>
> > Yes, you're right. For, say, a 3 x 5 design, one can do
> this i
gt; From: r-help-bounces at stat.math.ethz.ch
> [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of
> statistical.model at googlemail.com
> Sent: Monday, January 23, 2006 12:20 PM
> To: Berton Gunter; statistical.model at googlemail.com;
> r-help at stat.math.ethz.ch
> Subj
usiness of the statistician is to catalyze the scientific learning
>>process." - George E. P. Box
>>
>
>
>>-Original Message-----
>>From: r-help-bounces at stat.math.ethz.ch
>>[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of
>>statistical.mo
I think you need to add factors="all" to gen.factorial(), otherwise the
model df will be less than what you expect.
gen.orthogonal.design(c(2,2,3,3,3,3,2,2),numCards=16)
[EMAIL PROTECTED] wrote:
> sorry, some small mistakes in the previuos syntax. This works!
>
> design.test <- gen.orthogonal.d
