I am looking for some source of information, some articles about Robust ANCOVA. Can you suggest me something? And do you know any source that directly gives information about how to perform various robust ANCOVA with R?
I have seen a citation about Maxwell et al. 1993, an article called Analysis of Covariance but I do not find it!
I know Quinn and Keough, Experimental Design and Data Analysis for Biologists but they do not give much information about Robust ANCOVA.