collapse.groupedData: Collapse a groupedData Object
Description
If object has a single grouping factor, it is returned
unchanged. Else, it is summarized by the values of the
displayLevel grouping factor (or the combination of its values
and the values of the covariate indicated in preserve, if any is
present). The collapsed data is used to produce a new
groupedData object, with grouping factor given by the
displayLevel factor.
Usage
## S3 method for class 'groupedData':
collapse(object, collapseLevel, displayLevel,
outer, inner, preserve, FUN, subset, \dots)
Arguments
Value
a groupedData object with a single grouping factor given by the
displayLevel grouping factor, resulting from collapsing
object over the levels of the collapseLevel grouping
factor.
References
Pinheiro, J.C. and Bates, D.M. (1997) "Future Directions in
Mixed-Effects Software: Design of NLME 3.0" available at
http://franz.stat.wisc.edu/pub/NLME.