The Meaning of Interaction
The following paper is a useful discussion of interaction from a model-based parametric statistical point of view. The discussion of biological vs. statistical epistasis is poorly cited, however.
Wang X, Elston RC, Zhu X. The Meaning of Interaction. Hum Hered. 2010 Dec 8;70(4):269-277. [PubMed]
Although recent studies have attempted to dispel the confusion that exists in regard to the definition, analysis and interpretation of interaction in genetics, there still remain aspects that are poorly understood by non-statisticians. After a brief discussion of the definition of gene-gene interaction, the main part of this study addresses the fundamental meaning of statistical interaction and its relationship to measurement scale, disproportionate sample sizes in the cells of a two-way table and gametic phase disequilibrium.