Supermodularizability

We study the ordinal content of assuming supermodularity, including conditions under which a binary relation can be represented by a supermodular function. When applied to revealed-preference relations, our results imply that supermodularity is some times not refutable: A consumer's choices can be rationalized with a supermodular utility function if they can be rationalized with a monotonic utility function. Hence, supermodularity is not empirically distinguishable from monotonicity. We present applications to assortative matching, decision under uncertainty, and to testing production technologies.