%include data(fuel);
title 'Bisquare Robust Regression - Fuel data';

%robust(data=fuel,
	response=fuel,
	model=tax drivers road inc,
	id=state,
	proc=reg,
	out=resids,
	print=1 8);
	
proc plot data=resids;
	plot  _weight_ * (_resid_ _hat_) = state;