fun get_avg_attribut: Float do
		var counter = new Counter[MClassDef]
		var filter = new ModelFilter
		for mclassdef in collect_mclassdefs(filter) do
			var number_attributs = mclassdef.collect_intro_and_redef_mattributes(filter).length
			if number_attributs != 0 then counter[mclassdef] = number_attributs
		end
		return counter.avg + counter.std_dev
	end