factor.scope
Compute Allowed Changes in Adding to or Dropping from a Formula
Description
add.scope
and drop.scope
compute those terms that can be individually added to or dropped from a model while respecting the hierarchy of terms.
Usage
add.scope(terms1, terms2) drop.scope(terms1, terms2) factor.scope(factor, scope)
Arguments
terms1 | the terms or formula for the base model. |
terms2 | the terms or formula for the upper ( |
factor | the |
scope | a list with one or both components |
Details
factor.scope
is not intended to be called directly by users.
Value
For add.scope
and drop.scope
a character vector of terms labels. For factor.scope
, a list with components drop
and add
, character vectors of terms labels.
See Also
Examples
add.scope( ~ a + b + c + a:b, ~ (a + b + c)^3) # [1] "a:c" "b:c" drop.scope( ~ a + b + c + a:b) # [1] "c" "a:b"
Copyright (©) 1999–2012 R Foundation for Statistical Computing.
Licensed under the GNU General Public License.