Local Supermodularity and Unique Assortative Matching∗
نویسنده
چکیده
Likes tend to match with likes. Supermodularity or increasing differences is a sufficient condition for unique assortative matching. This paper derives a necessary and sufficient condition, Local Supermodularity, which is satisfied for a broad class of economies. Establishing conditions for uniqueness is desirable for the purpose of incentive compatibility in the design of markets, and it guarantees a well-identified problem when estimating a matching model. Moreover, no information is needed on the equilibrium prices or transfers between partners.
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