This help file describes how to use the menu for picking the cube portion from a central composite design.
Ulrike Groemping
Specify the name of the new cube only design (default: name of active design with
.cubeonly appended), and press OK. The resulting reduced design can be used
for effects plots of the cube portion etc. This is especially useful, if the star point
response values are not yet available, and preliminary analyses are to be run.
NOTE: If the intention is sequential experimentation (as is often the case), it is
usually more desirable to first specify a standalone cube with center points and analyze
that design, and to only append a star portion later, if needed.
While subsequent reduction of a central composite design to its cube portion
does work for many purposes, the resulting design is not as clean as a cube portion
created from scratch; for example, augmenting it with a star portion again will fail.
(This could of course be fixed, but this fix has low priority.)
WARNING: Package RcmdrPlugin.DoE has been subjected to some testing, but must still be considered a beta version. It is strongly recommended to always keep a master copy of your valuable experimental data safely stored without touching it. (This would even hold for a final version of any software, but is of course far more important for a beta version.
See also function pickcube for the
function that does the work