Data envelopment analysis (DEA) as a method of measuring the efficiency of decision-making units (DMUs) has become an attractive tool used in managerial decision-making in many real-world applications. However. like other sophisticated methods. the application of DEA to a selected decision problem is not straightforward and requires to be carried out in a sequence of successive phases. https://smokeysmountainfurnitureoutlets.shop/product-category/memory-foam-mattress/