Menu.ccdTab1 {RcmdrPlugin.DoE} | R Documentation |
Basic information for Box-Behnken designs
Central composite designs can have three (alpha=1
) or five levels in all factors
and are useful for fitting second order polynomials to experimental data
based on several quantitative response variables.
They can be used in a process of sequential experimentation, experimenting first with the
cube portion and later adding (a) star block(s).
For more information, look at the help file for function
ccd.design
from package DoE.wrapper
or at ccd
from package rsm.
orthogonal
(default)
or rotatable
define calculated alpha values with interesting statistical properties.
However, it must of course be checked whether these make practical sense. For example,
if the orthogonal alpha turns out to be 2 but experimentation beyond 1.5 does not make sense,
the number should be defined manually.
Ulrike Groemping
~put references to the literature/web site here ~
See also FrF2
for the function defining the cube portion
of the design ccd.augment
for the function that augments
the cube portion with the star points, also function ccd
from package
rsm for the function that underlies function ccd.augment
.