Design Objects
DESCRIPTION:
Objects of class "design" (typically) represent data from a designed experiment.
GENERATION:
These objects are generated by the following functions: design, fac.design, oa.design.
METHODS:
Generic functions that have methods for designs include: alias, plot, print.
INHERITANCE:
Objects of class "design" inherit from "data.frame".
STRUCTURE:
Objects of class "design" are just like data frames - each one is a list all of whose components have the same length, and have attributes row.names and names. Designs need have no attributes other than those for data frames.
DETAILS:
The assumption is that a "design" object starts life with all of its variables being factors; then one or more quantitative variables are added. Unless told otherwise, methods for designs tend to assume that the first quantitative variable found in the design should be the response.

They may have special information indicating that they were produced as fractional factorial designs or as orthogonal array designs (see fac.design or oa.design). The important function factor.names returns or sets the names for the factors and for their levels. It does not use an explicit attribute of this name, however. Instead, it uses the names of the design object and the levels of each factor variable.

SEE ALSO:
data.frame.object , data.frame , design , fac.design , oa.design, factor.names .