Menu.FrF2level {RcmdrPlugin.DoE}

Menu for generating regular fractional factorial 2-level designs

Description

With this menu, regular fractional factorial 2-level designs can be generated. The menu calls function FrF2 from package FrF2 and has been opened internally using the function shown in the usage section, which normal users will never have to deal with.

Usage

Menu.FrF2level()

Prior Remark for Windows users

The most important technical point about this menu and the R-Commander in general:
The R GUI should be installed with the Single Document Interface (SDI) mode instead of the default MDI mode. John Fox, the author of R-Commander, has described how to change MDI to SDI, if R has been installed in the wrong mode (https://socialsciences.mcmaster.ca/jfox/Misc/Rcmdr/installation-notes.html). It is strongly discouraged to run the R-Commander under the MDI mode, as it happens very frequently that windows suddenly disappear. They usually have iconized only and can be retrieved from the taskbar; nevertheless, this behavior can be very annoying and can be avoided by using R in SDI mode.

User form structure

This user form is structured as a notebook with several tabs, and each tab has its own specific help button. It is recommended to work through the tabs from left to right, although it is possible to switch between tabs back and forth.

If the checkbox “Activate Special Choices” is ticked, the user form gets additional tabs for requesting estimable 2-factor interactions, for block or split-plot details, and for hard-to-change factors. Also, some of the standard tabs get more content than otherwise. If you are not an expert in the statistical details of experimental design, it is normally best to not activate these additional choices. The standard choices are sufficient for many purposes.

The buttons to the right of the tabs store or load form settings (cf. next section) for the complete form with all tabs.

What happens when pressing OK?

On OK, the menu will create an experimental design as an R data frame with some attributes (desnum, run.order and design.info). The list design.info contains, among other things, the element creator, which contains the stored form.

If requested on the Export tab, the R workspace with ONLY the experimental design will be saved at the specified location with the ending rda, and an Excel-readable html-file or a csv-file will be generated, depending on the users choice. Alternatively, it is possible to permanently store an R workspace with ONLY the design later using the menu entry “Export design” from the “Design” menu, or the full R workspace can be stored using the appropriate entry in the “File” menu of R commander. The menu entry for loading the stored R workspace in a future session can be found under “Data Management”.

Storing and loading form settings

The settings of the form (all tabs) can be saved at any time with the button “Store form”, which generates an object (of class menu.design2FrF). The button “Load form” can be used for loading these settings into the form again in order to continue working on the entries. The purpose of this functionality: work can be safely interrupted, or a finished design can be modified after a team discussion or ...

The stored inputs will be an object within the R session. If they are to be kept for future R sessions, the R workspace must be stored on disk or on another storage medium (file type RData or rda). This can be done from the file menu of the R commander (usually the leftmost menu). The menu entry for loading the stored R workspace in a future session can be found under “Data Management”.

Within an R session, the latest stored form inputs are normally loaded automatically on next usage of the menu. If you want to restart fresh, the button “Reset form” sets everything to default again.

As pointed out above, if a design is actually generated by pressing the OK button, the menu settings are saved within the design object. The button “Load form” knows how to load the form settings from designs, so that it is not necessary to separately store the form settings in this case.

Author(s)

Ulrike Groemping

See Also

See Also FrF2 for the function behind this menu, catlg for the design catalogues underlying this menu, and Menu.2level for choice between regular fractional factorial designs and screening designs, and DoEGlossary for the DoE-related terminology used in this software or its documentation.

Examples

## running the menu with default settings corresponds to
Design.1 <- FrF2(8, 4)
## the stored code from the menu will look more complicated because it also lists
##     the defaults for all the other arguments