Modification of Tukeyʹs additivity test

In this paper we discuss testing for an interaction in the two-way ANOVA with just one observation per cell. The known results are reviewed and a simulation study is performed to evaluate type I and type II risks of the tests. It is shown that the Tukey and Mandel additivity tests have very low power in case of more general interaction scheme. A modification of Tukeyʹs test is developed to resolve this issue. All tests mentioned in the paper have been implemented in R package Additivity Tests.