Analysis of statistical interactions
The R add-on package statint provides the functions
plotcontrast(). In addition some data sets for the analysis of
statistical interactions are provided. An extensive demonstration of the functionality can be found in the package vignette.
For a detailed description of the underlying methodology the authors refer to:
Kitsche, A. and Schaarschmidt, F. (2014). Analysis of statistical interactions in factorial experiments. Journal of Agronomy and Crop Science.