An implementation of the Aligned Rank Transform technique for
factorial analysis (see references below for details) including models with
missing terms (unsaturated factorial models). The function first
computes a separate aligned ranked response variable for each effect of the
user-specified model, and then runs a classic ANOVA on each of the aligned
ranked responses. For further details, see Higgins, J. J. and Tashtoush, S.
(1994). An aligned rank transform test for interaction. Nonlinear World 1
(2), pp. 201-211. Wobbrock, J.O., Findlater, L., Gergle, D. and
Higgins,J.J. (2011). The Aligned Rank Transform for nonparametric factorial
analyses using only ANOVA procedures. Proceedings of the ACM Conference on
Human Factors in Computing Systems (CHI '11). New York: ACM Press, pp.
143-146.