I have been using rlm() in the MASS library in R with the redescending weights (using MM or Tukey's biweight function). I wanted to find the importance of each predictor in the fitted model. Can someone please point me to a resource on how to go about doing this?
I wanted to clarify that I am looking for finding the importance of each predictor in robust linear regression. I am aware of how these work for linear models but not for robust linear regression. The link pointed to does not specifically say if the relaimpo package is valid for robust linear regression.
I am not sure about using bootstrap methods because of the concern that the bootstrap method (which assumes that all observations are i.i.d.) may not hold in the presence of contamination. Therefore, I was preferably looking for a method which works without the bootstrap.
I also wanted to clarify that I am looking for some deeper explanation/understanding on how to go about doing it. Pointing to a R package is fine (even though this forum is not about R) but I am really wanting to understand how this is done.