For an incompatible patient-donor pair, kidney exchanges often forbid receipt-before-donation (the patient receives a kidney before the donor donates) and donation-before-receipt, causing a double-coincidence-of-wants problem. Our proposed algorithm, the Unpaired kidney exchange algorithm, uses...

Patients needing kidney transplants may have willing donors who cannot donate to them because of blood or tissue incompatibility. Incompatible patient-donor pairs can exchange donor kidneys with other such pairs. The situation facing such pairs resembles models of the "double coincidence of...

We introduce limited liability in a model with a continuum of ex ante identical agents who face aggregate and idiosyncratic income risk. These agents can trade a complete menu of contingent claims, but they cannot commit and shares in a Lucas tree serve as collateral to back up their...