We consider the problem of trade between a price setting party who has private information about the quality of a good and a price taker who may also have private information. We restrict attention to the case in which, under full information, it is efficient to trade only a subset of all...

In a bargaining setting with asymmetrically informed, inequity-averse parties, a fully efficient mechanism (i.e., the double auction) exists if and only if compassion is strong. Less compassionate parties do not trade in the double auction in the limit of strong envy.